Oracle11g版本中未归档隐藏参数

In this post,I will give a list of all undocumented parameters in Oracle 11g. Here is a query to see all the parameters (documented and undocumented) which contain the string you enter when prompted:

– Enter name of the parameter when prompted

SET linesize 235
col Parameter FOR a50
col SESSION FOR a28
col Instance FOR a55
col S FOR a1
col I FOR a1
col D FOR a1
col Description FOR a90

SELECT
 a.ksppinm "Parameter",
 decode(p.isses_modifiable,'FALSE',NULL,b.ksppstvl) "Session",
 c.ksppstvl "Instance",'F','TRUE','T') "S",
 decode(p.issys_modifiable,'T','IMMEDIATE','I','DEFERRED','D') "I",
 decode(p.isdefault,'T') "D",
 a.ksppdesc "Description"
FROM x$ksppi a,x$ksppcv b,x$ksppsv c,v$parameter p
WHERE a.indx = b.indx AND a.indx = c.indx
 AND p.name(+) = a.ksppinm
 AND UPPER(a.ksppinm) LIKE UPPER('%&1%')
ORDER BY a.ksppinm;

Enter value for 1:

Here is the list of all undocumented parameters in Oracle 11g :

ParaMETER NAME	ParaMETER VALUE	DESCRIPTION
_4031_dump_bitvec	67194879	bitvec to specify dumps prior to 4031 error
_4031_dump_interval	300	Dump 4031 error once for each n-second interval
_4031_max_dumps	100	Maximum number of 4031 dumps for this process
_4031_sga_dump_interval	3600	Dump 4031 SGA heapdump error once for each n-second interval
_4031_sga_max_dumps	10	Maximum number of SGA heapdumps
_NUMA_instance_mapping	Not specified	Set of nodes that this instance should run on
_NUMA_pool_size	aggregate size in bytes of NUMA pool
_PX_use_large_pool	FALSE	Use Large Pool as source of PX buffers
_UTL_FILE_FOLLOW_SYMLINKS	UTL_FILE backout event which allows UTL_FILE to open symlinks
__db_cache_size	314572800	Actual size of DEFAULT buffer pool for standard block size buffers
__dg_broker_service_names	pdb11_XPT	service names for broker use
__java_pool_size	20971520	Actual size in bytes of java pool
__large_pool_size	4194304	Actual size in bytes of large pool
__oracle_base	/u01/app/oracle	ORACLE_BASE
__pga_aggregate_target	209715200	Current target size for the aggregate PGA memory consumed
__sga_target	629145600	Actual size of SGA
__shared_io_pool_size	0	Actual size of shared IO pool
__shared_pool_size	281018368	Actual size in bytes of shared pool
__streams_pool_size	Actual size in bytes of streams pool
_abort_recovery_on_join	if TRUE,abort recovery on join reconfigurations
_accept_versions		List of parameters for rolling operation
_active_standby_fast_reconfiguration	TRUE	if TRUE optimize dlm reconfiguration for active/standby OPS
_adaptive_direct_read	Adaptive Direct Read
_adaptive_fetch_enabled	enable/disable adaptive fetch in parallel group by
_add_col_optim_enabled	Allows new add column optimization
_add_stale_mv_to_dependency_list	add stale mv to dependency list
_addm_auto_enable	governs whether ADDM gets run automatically after every AWR snapshot
_addm_skiprules	comma-separated list of ADDM nodes to skip
_addm_version_check	governs whether ADDM checks the input AWR snapshot version
_adjust_literal_replacement	If TRUE,we will adjust the sql/PLUS output
_affinity_on	enable/disable affinity at run time
_aiowait_timeouts	Number of aiowait timeouts before error is reported
_alert_expiration	604800	seconds before an alert message is moved to exception queue
_alert_message_cleanup	1	Enable Alert Message Cleanup
_alert_message_purge	Enable Alert Message Purge
_alert_post_background	Enable Background Alert Posting
_all_shared_dblinks	treat all dblinks as shared
_allocate_creation_order	should files be examined in creation order during allocation
_allocation_update_interval	3	interval at which successful search in L1 should be updated
_allow_commutativity	allow for commutativity of +,* when comparing expressions
_allow_drop_snapshot_standby_grsp	Allow dropping snapshot standby guaranteed restore point
_allow_error_simulation	Allow error simulation for testing
_allow_level_without_connect_by	allow level without connect by
_allow_read_only_corruption	allow read-only open even if database is corrupt
_allow_resetlogs_corruption	allow resetlogs even if it will cause corruption
_allow_sage_attr	Allow checking disk Group SAGE Attr
_allow_terminal_recovery_corruption	Finish terminal recovery even if it may cause corruption
_alternate_iot_leaf_block_split_points	enable alternate index-organized table leaf-block split-points
_always_anti_join	CHOOSE	always use this method for anti-join when possible
_always_semi_join	always use this method for semi-join when possible
_always_star_transformation	always favor use of star transformation
_app_ctx_vers	enable app ctx versioning
_aq_tm_scanlimit	scan limit for Time Managers to clean up IOT
_arch_corrupted_redo_log	Variable to simulate corruption errors during archivals
_arch_io_slaves	ARCH I/O slaves
_array_update_vector_read_enabled	Enable array update vector read
_ash_disk_filter_ratio	Ratio of the number of in-memory samples to the number of samples actually written to disk
_ash_disk_write_enable	To enable or disable Active Session History flushing
_ash_dummy_test_param	Oracle internal dummy ASH parameter used ONLY for testing!
_ash_eflush_trigger	66	The percentage above which if the in-memory ASH is full the emergency flusher will be triggered
_ash_enable	To enable or disable Active Session sampling and flushing
_ash_min_mmnl_dump	90	Minimum Time interval passed to consider MMNL Dump
_ash_sample_all	To enable or disable sampling every connected session including ones waiting for idle waits
_ash_sampling_interval	1000	Time interval between two successive Active Session samples in millisecs
_ash_size	1048618	To set the size of the in-memory Active Session History buffers
_asm_acd_chunks	initial ACD chunks created
_asm_allow_only_raw_disks	discovery only raw devices
_asm_allow_resilver_corruption	Enable disk resilvering for external redundancy
_asm_ausize	1048576	allocation unit size
_asm_blksize	4096	Metadata block size
_asm_compatibility	10.1	default ASM compatibility level
_asm_dbmsdg_nohdrchk	dbms_diskgroup.checkfile does not check block headers
_asm_disk_repair_time	14400	seconds to wait before dropping a failing disk
_asm_emulmax	10000	max number of concurrent disks to emulate I/O errors
_asm_emultimeout	timeout before emulation begins (in 3s ticks)
_asm_kfdpevent	KFDP event
_asm_kfioevent	KFIO event
_asm_libraries	ufs	library search order for discovery
_asm_maxio	Maximum size of individual I/O request
_asm_repairquantum	60	quantum (in 3s) used to compute elapsed time for disk drop
_asm_runtime_capability_volume_support	runtime capability for volume support returns supported
_asm_skip_resize_check	skip the checking of the clients for s/w compatibility for resize
_asm_stripesize	131072	ASM file stripe size
_asm_stripewidth	8	ASM file stripe width
_asm_wait_time	18	Max/imum time to wait before asmb exits
_asmlib_test	Osmlib test event
_asmsid	asm	ASM instance id
_assm_default	ASSM default
_async_recovery_claims	ims asynchronously
_async_recovery_reads		_async_ts_threshold	check tablespace thresholds asynchronously
_auto_assign_cg_for_sessions	auto assign CGs for sessions
_automatic_maintenance_test	Enable AUTOTASK Test Mode
_automemory_broker_interval	memory broker statistics gathering interval for auto memory
_autotask_max_window	480	Maximum Logical Maintenance Window Length in minutes
_autotask_min_window	15	Minimum Maintenance Window Length in minutes
_autotune_gtx_idle_time	600	idle time to trigger auto-shutdown a gtx background process
_autotune_gtx_interval	5	interval to autotune global transaction background processes
_autotune_gtx_threshold	auto-tune threshold for degree of global transaction concurrency
_avoid_prepare		_aw_row_source_enabled	Enables AW Row Source instead of collection iterator
_awr_corrupt_mode	AWR Corrupt Mode
_awr_disabled_flush_tables	disable flushing of specified AWR tables
_awr_flush_threshold_metrics	Enable/disable Flushing AWR Threshold Metrics
_awr_flush_workload_metrics	Enable/disable Flushing AWR Workload Metrics
_awr_mmon_cpuusage	Enable/disable AWR MMON cpu Usage Tracking
_awr_restrict_mode	AWR Restrict Mode
_awr_sql_child_limit	200	Setting for AWR sql Child Limit
_b_tree_bitmap_plans	enable the use of bitmap plans for tables even when the tables only have B-tree indexes
_backup_disk_io_slaves	BACKUP disk I/O slaves
_backup_encrypt_opt_mode	4294967294	specifies encryption block optimization mode
_backup_io_pool_size	memory to reserve from the large pool
_backup_kgc_bufsz	specifies buffer size to be used by BZIP2 compression
_backup_kgc_memlevel	specifies memory level for ZLIB compression
_backup_kgc_niters	specifies number of iterations done by BZIP2 compression
_backup_kgc_perflevel	specifies compression (performance) level for ZLIB compression
_backup_kgc_scheme	ZLIB	specifies compression scheme
_backup_kgc_type	specifies compression type used by kgc BZIP2 compression
_backup_kgc_windowbits	specifies window size for ZLIB compression
_backup_ksfq_bufcnt	number of the ksfq buffers used for backup/restore
_backup_ksfq_bufcnt_max	maximum number of the ksfq buffer used for backup/restore
_backup_ksfq_bufsz	size of the ksfq buffer used for backup/restore
_backup_max_gap_size	largest gap in an incremental/optimized backup buffer,in bytes
_bct_bitmaps_per_file	number of bitmaps to store for each datafile
_bct_buffer_allocation_max	104857600	maximum size of all change tracking buffer allocations,237); padding:6px 10px 6px 0px">_bct_buffer_allocation_min_extents	mininum number of extents to allocate per buffer allocation
_bct_buffer_allocation_size	2097152	size of one change tracking buffer allocation,237); padding:6px 10px 6px 0px">_bct_chunk_size	change tracking datafile chunk size,237); padding:6px 10px 6px 0px">_bct_crash_reserve_size	262144	change tracking reserved crash recovery SGA space,237); padding:6px 10px 6px 0px">_bct_file_block_size	block size of change tracking file,237); padding:6px 10px 6px 0px">_bct_file_extent_size	extent size of change tracking file,237); padding:6px 10px 6px 0px">_bct_fixtab_file	change tracking file for fixed tables
_bct_initial_private_dba_buffer_size	initial number of entries in the private change tracking dba buffers
_bct_public_dba_buffer_size	total size of all public change tracking dba buffers,237); padding:6px 10px 6px 0px">_bitmap_or_improvement_enabled	controls extensions to partition pruning for general predicates
_block_change_tracking	change tracking possible
_blocking_sess_graph_cache_size	blocking session graph cache size in bytes
_blocks_per_cache_server	64	number of consecutive blocks per global cache server
_bloom_filter_debug	debug level for bloom filtering
_bloom_filter_enabled	enables or disables bloom filter
_bloom_predicate_enabled	enables or disables bloom filter predicate pushdown
_bloom_pruning_enabled	Enable partition pruning using bloom filtering
_bloom_vector_elements	number of elements in a bloom filter vector
_bsln_adaptive_thresholds_enabled	Adaptive Thresholds Enabled
_bt_mmv_query_rewrite_enabled	allow rewrites with multiple MVs and base tables
_buffer_busy_wait_timeout	buffer busy wait time in centiseconds
_buffered_publisher_flow_control_threshold	Flow control threshold for buffered publishers except capture
_bufq_stop_flow_control	Stop enforcing flow control for buffered queues
_build_deferred_mv_skipping_mvlog_update	DEFERRED MV creation skipping MV log setup update
_bump_highwater_mark_count	how many blocks should we allocate per free list on advancing HWM
_bwr_for_flushed_pi		_cache_stats_monitor		_capture_buffer_size	65536	To set the size of the PGA I/O recording buffers
_capture_publisher_flow_control_threshold	Flow control threshold for capture publishers
_case_sensitive_logon	case sensitive logon enabled
_cgs_reconfig_timeout	CGS reconfiguration timeout interval
_cgs_send_timeout	CGS send timeout value
_cgs_tickets	CGS messaging tickets
_check_block_after_checksum	perform block check after checksum if both are turned on
_check_block_new_invariant_for_flashback	check block new invariant for flashback
_check_ts_threshold	check tablespace thresholds
_cleanup_rollback_entries	no. of undo entries to apply per transaction cleanup
_client_result_cache_bypass	bypass the client result cache
_close_cached_open_cursors	close cursors cached by PL/sql at each commit
_cluster_library	clss	cluster library selection
_clusterwide_global_transactions	enable/disable clusterwide global transactions
_collapse_wait_history	collapse wait history
_collect_undo_stats	Collect Statistics v$undostat
_column_compression_factor	Column compression ratio
_column_elimination_off	turn off predicate-only column elimination
_column_tracking_level	column usage tracking
_compilation_call_heap_extent_size	16384	Size of the compilation call heaps extents
_complex_view_merging	enable complex view merging
_compression_above_cache	number of recompression above cache for sanity check
_compression_advisor	Compression advisor
_compression_chain	50	percentage of chained rows allowed for Compression
_controlfile_block_size	control file block size in bytes
_controlfile_enqueue_dump	dump the system states after controlfile enqueue timeout
_controlfile_enqueue_holding_time	780	control file enqueue max holding time in seconds
_controlfile_enqueue_timeout	900	control file enqueue timeout in seconds
_controlfile_section_init_size	control file initial section size
_controlfile_section_max_expand	control file max expansion rate
_controlfile_update_check	OFF	controlfile update sanity check
_convert_set_to_join	enables conversion of set operator to join
_coord_message_buffer	parallel recovery coordinator side extra message buffer size
_corrupted_rollback_segments	corrupted undo segment list
_cost_equality_semi_join	enables costing of equality semi-join
_cp_num_hash_latches	connection pool number of hash latches
_cpu_to_io	divisor for converting cpu cost to I/O cost
_cr_grant_global_role		_cr_grant_local_role	AUTO	turn 3-way CR grants off,make it automatic,or turn it on
_cr_server_log_flush		_cursor_bind_capture_area_size	400	maximum size of the cursor bind capture area
_cursor_bind_capture_interval	interval (in seconds) between two bind capture for a cursor
_cursor_db_buffers_pinned	178	additional number of buffers a cursor can pin at once
_cursor_features_enabled	2	Shared cursor features enabled bits.
_cursor_plan_enabled	enable collection and display of cursor plans
_cursor_plan_hash_version	version of cursor plan hash value
_cursor_plan_unparse_enabled	enables/disables using unparse to build projection/predicates
_cursor_stats_bucket	Hash table buckets for cursor stats (2^).
_cursor_stats_heap	4	Heaps/latches for cursor stats.
_cvw_enable_weak_checking	enable weak view checking
_db_aging_cool_count	Touch count set when buffer cooled
_db_aging_freeze_cr	Make CR buffers always be too cold to keep in cache
_db_aging_hot_criteria	Touch count which sends a buffer to head of replacement list
_db_aging_stay_count	Touch count set when buffer moved to head of replacement list
_db_aging_touch_time	_db_always_check_system_ts	Always perform block check and checksum for System tablespace
_db_block_adjcheck	adjacent cache buffer checks – low blkchk overwrite parameter
_db_block_adjchk_level	adjacent cache buffer check level
_db_block_align_direct_read	Align Direct Reads
_db_block_bad_write_check	enable bad write checks
_db_block_buffers	27060	Number of database blocks cached in memory: hidden parameter
_db_block_cache_clone	Always clone data blocks on get (for debugging)
_db_block_cache_history	buffer header tracing (non-zero only when debugging)
_db_block_cache_history_level	buffer header tracing level
_db_block_cache_num_umap	number of unmapped buffers (for tracking swap calls on blocks)
_db_block_cache_protect	protect database blocks (true only when debugging)
_db_block_cache_protect_internal	protect database blocks (for strictly internal use only)
_db_block_check_for_debug	Check more and dump block before image for debugging
_db_block_check_objtyp	check objd and typ on cache disk read
_db_block_corruption_recovery_threshold	threshold number of block recovery attempts
_db_block_do_full_mbreads	do full block read even if some blocks are in cache
_db_block_hash_buckets	Number of database block hash buckets
_db_block_hash_latches	2048	Number of database block hash latches
_db_block_header_guard_level	number of extra buffer headers to use as guard pages
_db_block_hi_priority_batch_size	Fraction of writes for high priority reasons
_db_block_kNown_clean_pct	Initial Percentage of buffers to maintain kNown clean
_db_block_lru_latches	number of lru latches
_db_block_max_cr_dba	6	Maximum Allowed Number of CR buffers per dba
_db_block_max_scan_pct	40	Percentage of buffers to inspect when looking for free
_db_block_med_priority_batch_size	Fraction of writes for medium priority reasons
_db_block_numa	Number of NUMA nodes
_db_block_prefetch_fast_longjumps_enabled	Batched IO enable fast longjumps
_db_block_prefetch_limit	Prefetch limit in blocks
_db_block_prefetch_override	Prefetch force override in blocks
_db_block_prefetch_private_cache_enabled	Batched IO enable private cache
_db_block_prefetch_quota	Prefetch quota as a percent of cache size
_db_block_prefetch_skip_reading_enabled	Batched IO enable skip reading buffers
_db_block_table_scan_buffer_size	Size of shared table scan read buffer
_db_block_temp_redo	generate redo for temp blocks
_db_block_trace_protect	trace buffer protect calls
_db_block_vlm_check	check of rvlm mapping leaks (for debugging)
_db_block_vlm_leak_threshold	Threshold for allowable vlm leaks
_db_blocks_per_hash_latch	Number of blocks per hash latch
_db_cache_advice_batch_size	128	cache advisory simulation batch size
_db_cache_advice_sample_factor	cache advisory sampling factor
_db_cache_crx_check	check for costly crx examination functions
_db_cache_pre_warm	Buffer Cache Pre-Warm Enabled : hidden parameter
_db_cache_process_cr_pin_max	maximum number of cr pins a process may have
_db_change_notification_enable	enable db change notification
_db_disable_temp_encryption	Diable Temp Encryption for Spills
_db_fast_obj_check	enable fast object drop sanity check
_db_fast_obj_ckpt	enable fast object checkpoint
_db_fast_obj_truncate	enable fast object truncate
_db_file_direct_io_count	Sequential I/O buf size
_db_file_exec_read_count	multiblock read count for regular clients
_db_file_format_io_buffers	Block formatting I/O buf count
_db_file_noncontig_mblock_read_count	11	number of noncontiguous db blocks to be prefetched
_db_file_optimizer_read_count	_db_handles	750	System-wide simultaneous buffer operations
_db_handles_cached	Buffer handles cached each process
_db_hot_block_tracking	track hot blocks for hash latch contention
_db_index_block_checking	index block checking override parameter
_db_large_dirty_queue	25	Number of buffers which force dirty queue to be written
_db_lost_write_checking	Enable scn based lost write detection mechanism
_db_mttr_advice	ON	MTTR advisory
_db_mttr_partitions	number of partitions for MTTR advisory
_db_mttr_sample_factor	MTTR simulation sampling factor
_db_mttr_sim_target	MTTR simulation targets
_db_mttr_sim_trace_size	256	MTTR simulation trace size
_db_mttr_trace_to_alert	dump trace entries to alert file
_db_noarch_disble_optim	Image redo logging (NOARCHIVEMODE)
_db_num_evict_waitevents	number of evict wait events
_db_obj_enable_ksr	enable ksr in object checkpoint/reuse
_db_percent_hot_default	Percent of default buffer pool considered hot
_db_percent_hot_keep	Percent of keep buffer pool considered hot
_db_percent_hot_recycle	Percent of recycle buffer pool considered hot
_db_percpu_create_cachesize	size of cache created per cpu in deferred cache create
_db_recovery_temporal_file_dest	default database recovery temporal file location
_db_required_percent_fairshare_usage	percent of fairshare a processor group should always use
_db_row_overlap_checking	row overlap checking override parameter for data/index blocks
_db_todefer_cache_create	buffer cache deferred create
_db_writer_chunk_writes	Number of writes DBWR should wait for
_db_writer_coalesce_area_size	2293760	Size of memory allocated to dbwriter for coalescing writes
_db_writer_coalesce_write_limit	Limit on size of coalesced write
_db_writer_flush_imu	If FALSE,DBWR will not downgrade IMU txns for AGING
_db_writer_histogram_statistics	maintain dbwr histogram statistics in x$kcbbhs
_db_writer_max_writes	Max number of outstanding DB Writer IOs
_db_writer_nomemcopy_coalesce	Enable DBWR no-memcopy coalescing
_db_writer_verify_writes	Enable lost write detection mechanism
_dbg_proc_startup	debug process startup
_dbms_sql_security_level	Security level in DBMS_sql
_dbwr_async_io	Enable dbwriter asynchronous writes
_dbwr_scan_interval	dbwriter scan interval
_dbwr_tracing	Enable dbwriter tracing
_dde_flood_control_init	Initialize Flood Control at database open
_dead_process_scan_interval	PMON dead process scan interval
_deadlock_diagnostic_level	automatic deadlock resolution diagnostics level
_deadlock_resolution_incidents_enabled	create incidents during deadlock resolution
_deadlock_resolution_level	automatic deadlock resolution level
_deadlock_resolution_min_wait_timeout_secs	the minimum wait timeout required for deadlock resolution
_deadlock_resolution_signal_process_thresh_secs	the amount of time given to process a deadlock resolution signal
_dedicated_server_poll_count	dedicated server poll count
_dedicated_server_post_wait	dedicated server post/wait
_dedicated_server_post_wait_call	dedicated server post/wait call
_default_encrypt_alg	default encryption algorithm
_default_non_equality_sel_check	sanity check on default selectivity for like/range predicate
_defer_log_boundary_ckpt	defer media recovery checkpoint at log boundary
_defer_log_count	Number of log boundaries media recovery checkpoint lags behind
_delay_index_maintain	delays index maintenance until after MV is refreshed
_desired_readmem_rate	70	The desired percentage of redo reading from memory
_diag_adr_auto_purge	Enable/disable ADR MMON Auto Purging
_diag_adr_enabled	Parameter to enable/disable Diag ADR
_diag_adr_test_param	Test parameter for Diagnosability
_diag_backward_compat	Backward Compatibility for Diagnosability
_diag_cc_enabled	Parameter to enable/disable Diag Call Context
_diag_conf_cap_enabled	Parameter to enable/disable Diag Configuration Capture
_diag_daemon	start DIAG daemon
_diag_dde_async_age_limit	diag dde async actions: message age limit (in seconds)
_diag_dde_async_cputime_limit	diag dde async actions: action cputime limit (in seconds)
_diag_dde_async_mode	diag dde async actions: dispatch mode
_diag_dde_async_msg_capacity	1024	diag dde async actions: message buffer capacity
_diag_dde_async_msgs	diag dde async actions: number of preallocated message buffers
_diag_dde_async_process_rate	diag dde async actions: message processing rate – per loop
_diag_dde_async_runtime_limit	diag dde async actions: action runtime limit (in seconds)
_diag_dde_async_slaves	diag dde async actions: max number of concurrent slave processes
_diag_dde_enabled	enable DDE handling of critical errors
_diag_dde_fc_enabled	Parameter to enable/disable Diag Flood Control
_diag_dde_fc_implicit_time	Override Implicit Error Flood Control time parameter
_diag_dde_fc_macro_time	Override Macro Error Flood Control time parameter
_diag_dde_inc_proc_delay	The minimum delay between two MMON incident sweeps (minutes)
_diag_diagnostics	Turn off diag diagnostics
_diag_dump_timeout	30	timeout parameter for SYNC dump
_diag_hm_rc_enabled	Parameter to enable/disable Diag HM Reactive Checks
_diag_hm_tc_enabled	Parameter to enable/disable Diag HM Test(dummy) Checks
_diag_uts_control	UTS control parameter
_dimension_skip_null	control dimension skip when null feature
_direct_path_insert_features	disable direct path insert features
_disable_12751	disable policy timeout error (ORA-12751)
_disable_adaptive_shrunk_aggregation	adaptive shrunk aggregation
_disable_autotune_gtx	disable autotune global transaction background processes
_disable_datalayer_sampling	disable datalayer sampling
_disable_duplex_link	Turn off connection duplexing
_disable_fast_aggregation	fast aggregation
_disable_fast_validate	disable PL/sql fast validation
_disable_fastopen	Do Not Use Fastopen
_disable_fba_qrw	disable flashback archiver query rewrite
_disable_fba_wpr	disable flashback archiver wait for prepared transactions
_disable_file_locks	disable file locks for control,data,redo log files
_disable_flashback_archiver	disable flashback archiver
_disable_flashback_wait_callback	disable flashback wait callback
_disable_function_based_index	disable function-based index matching
_disable_health_check	disable Health Check
_disable_highres_ticks	disable high-res tick counter
_disable_image_check	disable Oracle executable image checking
_disable_incremental_checkpoints	disable incremental checkpoints for thread recovery
_disable_incremental_recovery_ckpt	disable incremental recovery checkpoint mechanism
_disable_index_block_prefetching	disable index block prefetching
_disable_instance_params_check	disable instance type check for ksp
_disable_interface_checking	disable interface checking at startup
_disable_kcb_flashback_blocknew_opt	disable KCB flashback block new optimization
_disable_kcbhxor_osd	disable kcbh(c)xor OSD functionality
_disable_kcbl_flashback_blocknew_opt	disable KCBL flashback block new optimization
_disable_latch_free_SCN_writes_via_32cas	disable latch-free SCN writes using 32-bit compare & swap
_disable_latch_free_SCN_writes_via_64cas	disable latch-free SCN writes using 64-bit compare & swap
_disable_logging	disable logging
_disable_metrics_group	disable Metrics Group (or all Metrics Groups)
_disable_multiple_block_sizes	disable multiple block size support (for debugging)
_disable_odm	disable odm feature
_disable_parallel_conventional_load	disable parallel conventional loads
_disable_read_only_open_dict_check	disable read-only open dictionary check
_disable_rebalance_space_check	disable space usage checks for storage reconfiguration
_disable_recoverable_recovery	disable the new recoverable recovery mechanism
_disable_recovery_read_skip	disable the read optimization during media recovery
_disable_sample_io_optim	disable row sampling IO optimization
_disable_savepoint_reset	disable the fix for bug 1402161
_disable_sec_ticks	disable low-res (sec) counter
_disable_selftune_checkpointing	disable self-tune checkpointing
_disable_streams_pool_auto_tuning	disable streams pool auto tuning
_disable_sun_rsm	disable IPC OSD support for Sun RSMAPI
_disable_system_state	disable system state dump
_disable_thread_internal_disable	disable thread internal disable feature
_disable_txn_alert	disable txn layer alert
_disable_vktm	disable vktm process
_disable_wait_stack	disable wait stack
_discrete_transactions_enabled	enable OLTP mode
_diskmon_pipe_name	disKMon skgznp pipe name
_dispatcher_rate_scale	scale to display rate statistic (100ths of a second)
_dispatcher_rate_ttl	time-to-live for rate statistic (100ths of a second)
_distinct_view_unnesting	enables unnesting of in subquery into distinct view
_distributed_recovery_connection_hold_time	number of seconds RECO holds outbound connections open
_dlmtrace	Trace string of global enqueue type(s)
_dm_max_shared_pool_pct	max percentage of the shared pool to use for a mining model
_dml_monitoring_enabled	enable modification monitoring
_domain_index_batch_size	2000	maximum number of rows from one call to domain index fetch routine
_domain_index_dml_batch_size	maximum number of rows for one call to domain index dml routines
_dra_bmr_number_threshold	Maximum number of BMRs that can be done to a file
_dra_bmr_percent_threshold	Maximum percentage of blocks in a file that can be BMR-ed
_dra_enable_offline_dictionary	Enable the periodic creation of the offline dictionary for DRA
_drop_table_granule	drop_table_granule
_drop_table_optimization_enabled	reduce SGA memory use during drop of a partitioned table
_ds_iocount_iosize	6553664	Dynamic Sampling Service defaults: #IOs and IO Size
_dss_cache_flush	enable full cache flush for parallel execution
_dtree_area_size	size of Decision Tree Classification work area
_dtree_binning_enabled	Decision Tree Binning Enabled
_dtree_bintest_id	Decision Tree Binning Test ID
_dtree_compressbmp_enabled	Decision Tree Using Compressed Bitmaps Enabled
_dtree_max_surrogates	maximum number of surrogates
_dtree_pruning_enabled	Decision Tree Pruning Enabled
_dummy_instance	dummy instance started by RMAN
_dump_common_subexpressions	dump common subexpressions
_dump_connect_by_loop_data	dump connect by loop error message into trc file
_dump_cursor_heap_sizes	dump comp/exec heap sizes to tryace file
_dump_interval_limit	120	trace dump time interval limit (in seconds)
_dump_max_limit	max number of dump within dump interval
_dump_qbc_tree	dump top level query parse tree to trace
_dump_rcvr_ipc	if TRUE enables IPC dump at instance eviction time
_dump_system_state_scope	local	scope of sysstate dump during instance termination
_dump_trace_scope	global	scope of trace dump during a process crash
_dynamic_rls_policies	rls policies are dynamic
_dynamic_stats_threshold	delay threshold (in seconds) between sending statistics messages
_edition_based_redeFinition	enable edition based redeFinition
_eliminate_common_subexpr	enables elimination of common sub-expressions
_emon_regular_ntfn_slaves	number of EMON slaves doing regular database notifications
_enable_NUMA_optimization	Enable NUMA specific optimizations
_enable_automatic_maintenance	if 1,Automated Maintenance Is Enabled
_enable_automatic_sqltune	Automatic sql Tuning Advisory enabled parameter
_enable_block_level_transaction_recovery	enable block level recovery
_enable_cscn_caching	enable commit SCN caching for all transactions
_enable_ddl_wait_lock	use this to turn off ddls with wait semantics
_enable_default_affinity	to enable default implementation of affinity osds
_enable_dml_lock_escalation	enable dml lock escalation against partitioned tables if TRUE
_enable_exchange_validation_using_check	use check constraints on the table for validation
_enable_fast_ref_after_mv_tbs	enable fast refresh after move tablespace
_enable_hash_overflow	TRUE – enable hash cluster overflow based on SIZE
_enable_hwm_sync	enable HWM synchronization
_enable_list_io	Enable List I/O
_enable_midtier_affinity	enable midtier affinity metrics processing
_enable_nativenet_tcpip	Enable skgxp driver usage for native net
_enable_obj_queues	enable object queues
_enable_online_index_without_s_locking	Allow online index creation algorithm without S DML lock
_enable_query_rewrite_on_remote_objs	mv rewrite on remote table/view
_enable_refresh_schedule	enable or disable MV refresh scheduling (revert to 9.2 behavior)
_enable_reliable_latch_waits	Enable reliable latch waits
_enable_rlb	enable RLB metrics processing
_enable_row_shipping	use the row shipping optimization for wide table selects
_enable_scn_wait_interface	use this to turn off scn wait interface in kta
_enable_separable_transactions	enable/disable separable transactions
_enable_shared_pool_durations	temporary to disable/enable kgh policy
_enable_shared_server_vector_io	Enable shared server vector I/O
_enable_space_preallocation	enable space pre-allocation
_enable_spacebg	enable space management background task
_enable_tablespace_alerts	enable tablespace alerts
_enable_type_dep_selectivity	enable type dependent selectivity estimates
_endprot_chunk_comment	chk 10235 dflt	chunk comment for selective overrun protection
_endprot_heap_comment	hp 10235 dflt	heap comment for selective overrun protection
_endprot_subheaps	selective overrun protection for subeheaps
_enqueue_deadlock_time_sec	requests with timeout <= this will not have deadlock detection
_enqueue_debug_multi_instance	debug enqueue multi instance
_enqueue_hash	375	enqueue hash table length
_enqueue_hash_chain_latches	enqueue hash chain latches
_enqueue_locks	2260	locks for managed enqueues
_enqueue_resources	968	resources for enqueues
_evolve_plan_baseline_report_level	TYPICAL	Level of detail to show in plan verification/evolution report
_evt_system_event_propagation	disable system event propagation
_expand_aggregates	expand aggregates
_explain_rewrite_mode	allow additional messages to be generated during explain rewrite
_extended_pruning_enabled	do runtime pruning in iterator if set to TRUE
_fair_remote_cvt	if TRUE enables fair remote convert
_fairness_threshold	number of times to CR serve before downgrading lock
_fast_dual_enabled	enable/disable fast dual
_fast_full_scan_enabled	enable/disable index fast full scan
_fastpin_enable	enable reference count based fast pins
_fbda_busy_percentage	flashback archiver busy percentage
_fbda_inline2_percentage	flashback archiver full inline percentage
_fbda_inline_percentage	flashback archiver inline percentage
_fg_iorm_slaves	ForeGround I/O slaves for IORM
_fg_log_checksum	Checksum redo in foreground process
_fic_algorithm_set	automatic	Set Frequent Itemset Counting Algorithm
_fic_area_size	size of Frequent Itemset Counting work area
_fic_max_length	20	Frequent Itemset Counting Maximum Itemset Length
_fic_min_bmsize	Frequent Itemset Counting Minimum BITMAP Size
_fic_outofmem_candidates	Frequent Itemset Counting Out Of Memory Candidates Generation
_fifth_spare_parameter	fifth spare parameter – string
_filemap_dir	FILEMAP directory
_first_k_rows_dynamic_proration	enable the use of dynamic proration of join cardinalities
_first_spare_parameter	first spare parameter – integer
_fix_control	bug fix control parameter
_flashback_allow_noarchivelog	Allow enabling flashback on noarchivelog database
_flashback_archiver_partition_size	flashback archiver table partition size
_flashback_barrier_interval	1800	Flashback barrier interval in seconds
_flashback_copy_latches	Number of flashback copy latches
_flashback_format_chunk_mb	Chunk mega-bytes for formatting flashback logs using sync write
_flashback_format_chunk_mb_dwrite	16	Chunk mega-bytes for formatting flashback logs using delayed write
_flashback_fuzzy_barrier	Use flashback fuzzy barrier
_flashback_generation_buffer_size	flashback generation buffer size
_flashback_hint_barrier_percent	Flashback hint barrier percent
_flashback_log_io_error_behavior	Specify Flashback log I/O error behavior
_flashback_log_min_size	Minimum flashback log size
_flashback_log_size	Flashback log size
_flashback_logfile_enqueue_timeout	flashback logfile enqueue timeout for opens
_flashback_marker_cache_enabled	Enable flashback database marker cache
_flashback_marker_cache_size	328	Size of flashback database marker cache
_flashback_max_log_size	Maximum flashback log size in bytes (OS limit)
_flashback_max_n_log_per_thread	Maximum number of flashback logs per flashback thread
_flashback_max_standby_sync_span	Maximum time span between standby recovery sync for flashback
_flashback_n_log_per_thread	Desired number of flashback logs per flashback thread
_flashback_standby_barrier_interval	Flashback standby barrier interval in seconds
_flashback_verbose_info	Print verbose information about flashback database
_flashback_write_max_loop_limit	Flashback writer loop limit before it returns
_force_datefold_trunc	force use of trunc for datefolding rewrite
_force_hsc_compress	compress all new created tables
_force_oltp_compress	OLTP Compress all new created tables
_force_rewrite_enable	control new query rewrite features
_force_slave_mapping_intra_part_loads	Force slave mapping for intra partition loads
_force_temptables_for_gsets	executes concatenation of rollups using temp tables
_force_tmp_segment_loads	Force tmp segment loads
_forwarded_2pc_threshold	auto-tune threshold for two-phase commit rate across RAC instances
_fourth_spare_parameter	fourth spare parameter – string
_full_pwise_join_enabled	enable full partition-wise join when TRUE
_gby_hash_aggregation_enabled	enable group-by and aggregation using hash scheme
_gby_onekey_enabled	enable use of one comparison of all group by keys
_gc_affinity_locking		_gc_affinity_locks		_gc_affinity_ratio	dynamic object affinity ratio
_gc_async_memcpy	cpy
_gc_bypass_readers		_gc_check_bscn		_gc_coalesce_recovery_reads		_gc_defer_time	how long to defer down converts for hot buffers
_gc_dissolve_undo_affinity	dissolve undo affinity after an offline
_gc_element_percent	110	global cache element percent
_gc_global_checkpoint_scn		_gc_global_lru	turn global lru off,237); padding:6px 10px 6px 0px">_gc_initiate_undo_affinity		_gc_integrity_checks	set the integrity check level
_gc_keep_recovery_buffers		_gc_latches	number of latches per LMS process
_gc_long_query_threshold	threshold for long running query
_gc_maximum_bids	maximum number of bids which can be prepared
_gc_policy_minimum	1500	dynamic object policy minimum activity per minute
_gc_policy_time	how often to make object policy decisions in minutes
_gc_read_mostly_locking		_gc_statistics		_gc_transfer_ratio	dynamic object read-mostly transfer ratio
_gc_undo_affinity		_gc_undo_block_disk_reads	disk reads
_gc_use_cr		_gc_vector_read		_gc_voluntary_down_convert_obj	object number for voluntary down-convert
_gcs_fast_reconfig	figuration for gcs locks
_gcs_latches	number of gcs resource hash latches to be allocated per LMS process
_gcs_process_in_recovery		_gcs_res_per_bucket	number of gcs resource per hash bucket
_gcs_resources	number of gcs resources to be allocated
_gcs_shadow_locks	number of pcm shadow locks to be allocated
_gcs_testing	GCS testing parameter
_generalized_pruning_enabled	_ges_dd_debug	if 1 or higher enables GES deadlock detection debug diagnostics
_ges_diagnostics	if TRUE enables GES diagnostics
_ges_health_check	if greater than 0 enables GES system health check
_global_hang_analysis_interval_secs	the interval at which global hang analysis is run
_globalindex_pnum_filter_enabled	enables filter for global index with partition extended Syntax
_groupby_nopushdown_cut_ratio	groupby nopushdown cut ratio
_groupby_orderby_combine	5000	groupby/orderby don’t combine threshold
_gs_anti_semi_join_allowed	enable anti/semi join for the GS query
_hang_analysis_num_call_stacks	hang analysis num call stacks
_hang_detection	Hang Management detection interval
_hang_resolution	Hang Management hang resolution
_hard_protection	if TRUE enable H.A.R.D specific format changes
_hash_join_enabled	enable/disable hash join
_hash_multiblock_io_count	number of blocks hash join will read/write at once
_heur_deadlock_resolution_secs	the heuristic wait time per node for deadlock resolution
_high_priority_processes	LMS*|VKTM	High Priority Process Name Mask
_high_server_threshold	high server thresholds
_hj_bit_filter_threshold	hash-join bit filtering threshold (0 always enabled)
_hm_analysis_oradebug_node_dump_level	the oradebug node dump level for hang manager hang analysis
_hm_analysis_oradebug_sys_dump_level	the oradebug system state level for hang manager hang analysis
_hm_analysis_output_disk	if TRUE the hang manager outputs hang analysis results to disk
_hm_log_incidents	Hang Manager incident logging
_hm_verification_interval	the hang manager verification interval
_hwm_sync_threshold	HWM synchronization threshold in percentage
_idl_conventional_index_maintenance	enable conventional index maintenance for insert direct load
_idle_session_kill_enabled	enables or disables resource manager session idle limit checks
_idxrb_rowincr	100000000	proportionality constant for dop vs. rows in index rebuild
_ignore_desc_in_index	ignore DESC in indexes,sort those columns ascending anyhow
_ignore_fg_deps	ignore fine-grain dependencies during invalidation
_immediate_commit_propagation		_improved_outerjoin_card	improved outer-join cardinality calculation
_improved_row_length_enabled	enable the improvements for computing the average row length
_imr_active	Activate Instance Membership Recovery feature
_imr_avoid_double_voting	Avoid device voting for CSS reconfig during IMR
_imr_device_type	controlfile	Type of device to be used by IMR
_imr_disk_voting_interval	Maximum wait for IMR disk voting (seconds)
_imr_evicted_member_kill	IMR issue evicted member kill after a wait
_imr_evicted_member_kill_wait	IMR evicted member kill wait time in seconds
_imr_highload_threshold	IMR system highload threshold
_imr_max_reconfig_delay	Maximum Reconfiguration delay (seconds)
_imr_splitbrain_res_wait	Maximum wait for split-brain resolution (seconds)
_imr_systemload_check	Perform the system load check during IMR
_imu_pools	in memory undo pools
_in_memory_undo	Make in memory undo for top level transactions
_incremental_recovery_ckpt_min_batch	Minimum number of writes for incremental recovery ckpt every 3 sec
_index_join_enabled	enable the use of index joins
_index_prefetch_factor	index prefetching factor
_init_granule_interval	number of granules to process for deferred cache
_init_sql_file	?/rdbms/admin/sql.bsq	File containing sql statements to execute upon database creation
_inject_startup_fault	inject fault in the startup code
_inline_sql_in_plsql	inline sql in PL/sql
_insert_enable_hwm_brokered	during parallel inserts high water marks are brokered
_inst_locking_period	period an instance can retain a newly acquired level1 bitmap
_interconnect_checksum		_intrapart_pdml_enabled	Enable intra-partition updates/deletes
_intrapart_pdml_randomlocal_enabled	Enable intra-partition updates/deletes with random local dist
_io_resource_manager_always_on	io resource manager always on
_io_shared_pool_size	Size of I/O buffer pool from SGA
_io_slaves_disabled	Do not use I/O slaves
_io_statistics	I/O statistics are collected
_ioq_fanin_multiplier	IOQ miss count before a miss exception
_ior_serialize_fault	inject fault in the ior serialize code
_iorm_tout	IORM scheduler timeout value in msec
_ioslave_batch_count	Per attempt IOs picked
_ioslave_issue_count	500	IOs issued before completion check
_ipc_fail_network	Simulate cluster network failer
_ipc_test_failover	Test transparent cluster network failover
_ipc_test_mult_nets	simulate multiple cluster networks
_job_queue_interval	Wakeup interval in seconds for job queue co-ordinator
_k2q_latches	number of k2q latches
_kcfis_fault_control	trace level setting for kcfIS module
_kcfis_max_appliances	Max. appliances in a kcfIS session
_kcfis_oss_io_size	kcfIS OSS I/O size
_kcfis_read_buffer_limit	kcfIS Read Buffer (per session) memory limit in bytes
_kcfis_trace_level	_kcfis_work_set_appliances	Working Set of appliances in a kcfIS session
_kcl_commit		_kcl_conservative_log_flush		_kcl_debug		_kcl_index_split		_kdbl_enable_post_allocation	allocate dbas after populating data buffers
_kdi_avoid_block_checking	avoid index block checking on sensitive opcodes
_kdli_STOP_bsz	undocumented parameter for internal use only
_kdli_STOP_dba	_kdli_STOP_fsz	_kdli_STOP_nio	_kdli_STOP_tsn	_kdli_allow_corrupt	allow corrupt filesystem_logging data blocks during read/write
_kdli_cache_inode	cache inode state across calls
_kdli_cache_read_threshold	minimum lob size for cache->nocache read (0 disables heuristic)
_kdli_cache_size	maximum #entries in inode cache
_kdli_cache_verify	verify cached inode via deserialization
_kdli_cache_write_threshold	minimum lob size for cache->nocache write (0 disables heuristic)
_kdli_cacheable_length	minimum lob length for inode cacheability
_kdli_force_cr	force CR when reading data blocks of direct-write lobs
_kdli_force_cr_Meta	force CR when reading Metadata blocks of direct-write lobs
_kdli_force_storage	none	force storage settings for all lobs
_kdli_full_readahead_threshold	maximum lob size for full readahead
_kdli_inject_assert	inject asserts into the inode
_kdli_inject_crash	inject crashes into the inode
_kdli_inline_xfm	allow inline transformed lobs
_kdli_inode_preference	data	inline inode evolution preference (data,headless,lhb)
_kdli_itree_entries	#entries in lhb/itree blocks (for testing only)
_kdli_memory_protect	trace accesses to inode memory outside kdli API functions
_kdli_rci_lobmap_entries	255	#entries in RCI lobmap before migration to lhb
_kdli_readahead_limit	shared/cached IO readahead limit
_kdli_readahead_strategy	contig	shared/cached IO readahead strategy
_kdli_recent_scn	use recent (not dependent) scns for block format/allocation
_kdli_reshape	reshape an inode to inline or headless on length truncation
_kdli_safe_callbacks	invoke inode read/write callbacks safely
_kdli_sio_async	asynchronous shared IO
_kdli_sio_backoff	use exponential backoff when attempting SIOP allocations
_kdli_sio_bps	maximum blocks per IO slot
_kdli_sio_dop	degree-of-parallelism in the SIO keep pool
_kdli_sio_fgio	reap asynchronous IO in the foreground
_kdli_sio_fileopen	nodsync	shared IO fileopen mode: datasync vs nodatasync vs async
_kdli_sio_flush	enable shared IO pool operations
_kdli_sio_free	free IO buffers when not in active use
_kdli_sio_min_read	shared IO pool read threshold
_kdli_sio_min_write	shared IO pool write threshold
_kdli_sio_nbufs	maximum #IO buffers to allocate per session
_kdli_sio_niods	maximum #IO descriptors to allocate per session
_kdli_sio_on	_kdli_sio_pga	use PGA allocations for direct IO
_kdli_sio_pga_top	PGA allocations come from toplevel PGA heap
_kdli_sio_strategy	auto	shared IO strategy: block vs. extent
_kdli_small_cache_limit	32	size limit of small inode cache
_kdli_sort_dbas	sort dbas during chunkification
_kdli_space_cache_limit	maximum size of the space cache in #blocks
_kdli_squeeze	compact lobmap extents with contiguous dbas
_kdli_timer_dmp	dump inode timers on session termination
_kdli_timer_trc	trace inode timers to uts/tracefile
_kdli_trace	inode trace level
_kdlu_max_bucket_size	UTS kdlu bucket size
_kdlu_max_bucket_size_mts	UTS kdlu bucket size for mts
_kdlu_trace_layer	UTS kdlu per-layer trace level
_kdlu_trace_session	UTS session dump
_kdlu_trace_system	UTS system dump
_kdlw_enable_ksi_locking	enable ksi locking for lobs
_kdlw_enable_write_gathering	enable lob write gathering for sql txns
_kdlwp_flush_threshold	WGC flush threshold in bytes
_kdlxp_cmp_subunit_size	size of compression sub-unit in bytes
_kdlxp_dedup_flush_threshold	8388608	deduplication flush threshold in bytes
_kdlxp_dedup_hash_algo	SHA1	secure hash algorithm for deduplication – only on SecureFiles
_kdlxp_dedup_prefix_threshold	deduplication prefix hash threshold in bytes
_kdlxp_lobcompress	enable lob compression – only on SecureFiles
_kdlxp_lobdeduplicate	enable lob deduplication – only on SecureFiles
_kdlxp_lobdedupvalidate	enable deduplicate validate – only on SecureFiles
_kdlxp_lobencrypt	enable lob encryption – only on SecureFiles
_kdlxp_min_xfm_size	32768	minimum transformation size in bytes
_kdlxp_mincmp	minimum comp ratio in pct – only on SecureFiles
_kdlxp_spare1	deduplication spare 1
_kdlxp_xfmcache	enable xfm cache – only on SecureFiles
_kdt_buffering	control kdt buffering for conventional inserts
_kebm_nstrikes	kebm # strikes to auto suspend an action
_kebm_suspension_time	82800	kebm auto suspension time in seconds
_keep_remote_column_size	remote column size does not get modified
_kernel_message_network_driver	kernel message network driver
_kffmap_hash_size	size of kffmap_hash table
_kffmop_hash_size	size of kffmop_hash table
_kfm_disable_set_fence	disable set fence calls and revert to default (process fence)
_kghdsidx_count	max kghdsidx count
_kgl_bucket_count	9	index to the bucket count array
_kgl_debug	Library cache debugging
_kgl_features_enabled	Library cache features enabled bits
_kgl_fixed_extents	fixed extent size for library cache memory allocations
_kgl_hash_collision	whether KGL hash collision is possible
_kgl_heap_size	extent size for library cache heap 0
_kgl_kqr_cap_so_stacks	capture stacks for library and row cache state objects
_kgl_large_heap_warning_threshold	52428800	maximum heap size before KGL writes warnings to the alert log
_kgl_latch_count	number of library cache latches
_kgl_message_locks	RAC message lock count
_kgl_min_cached_so_count	Minimum cached SO count. If > 1 can help find SO corruptions
_kgl_multi_instance_invalidation	whether KGL to support multi-instance invalidations
_kgl_multi_instance_lock	whether KGL to support multi-instance locks
_kgl_multi_instance_pin	whether KGL to support multi-instance pins
_kgl_so_stack_depth	The depth of the stack capture for SO get or free
_kgl_time_to_wait_for_locks	time to wait for locks and pins before timing out
_kglsim_maxmem_percent	max percentage of shared pool size to be used for KGL advice
_kgsb_threshold_size	16777216	threshold size for base allocator
_kgx_latches	# of mutex latches if CAS is not supported.
_kgx_spin_count	third spare parameter – integer
_kill_controlfile_enqueue_blocker	enable killing controlfile enqueue blocker on timeout
_kill_diagnostics_timeout	timeout delay in seconds before killing enqueue blocker
_kill_enqueue_blocker	if greater than 0 enables killing enqueue blocker
_kill_java_threads_on_eoc	Kill Java threads and do sessionspace migration at end of call
_kill_session_dump	Process dump on kill session immediate
_kkdlgon_max_iter	20000	kkdlgon maximum number of iterations
_kkfi_trace	trace expression substitution
_kks_free_cursor_stat_pct	percentage of cursor stats buckets to scan on each load,in 1/10th of a percent
_kks_use_mutex_pin	Turning on this will make KKS use mutex for cursor pins.
_kokli_cache_size	Size limit of Materialized View and Object Table Lookup Cache
_kolfuseslf	allow kolf to use slffopen
_kql_subheap_trace	tracing level for library cache subheap level pins
_ksb_disable_diagpid	disable the call to ksb_diagpid
_ksb_restart_clean_time	30000	process uptime for restarts
_ksb_restart_policy_times	0,60,120,240	process restart policy times in seconds
_ksd_test_param	999	KSD test parmeter
_ksdxdocmd_default_timeout_ms	default timeout for internal oradebug commands
_ksdxdocmd_enabled	if TRUE ksdxdocmd* invocations are enabled
_ksdxw_cini_flg	ksdxw context initialization flag
_ksdxw_nbufs	ksdxw number of buffers in buffered mode
_ksdxw_num_pgw	number of watchpoints on a per-process basis
_ksdxw_num_sgw	number of watchpoints to be shared by all processes
_ksdxw_stack_depth	number of PCs to collect in the stack when watchpoint is hit
_kse_die_timeout	60000	amount of time a dying process is spared by PMON (in centi-secs)
_kse_pc_table_size	kse pc table cache size
_kse_signature_entries	number of entries in the kse stack signature cache
_kse_signature_limit	7	number of stack frames to cache per kse signature
_kse_snap_ring_size	ring buffer to debug internal error 17090
_ksfd_verify_write	verify asynchronous writes issued through ksfd
_ksi_trace	KSI trace string of lock type(s)
_ksi_trace_bucket	PRIVATE	memory tracing: use ksi-private or rdbms-shared bucket
_ksi_trace_bucket_size	8192	size of the KSI trace bucket
_ksmb_debug	ksmb debug flags
_ksmd_protect_mode	off	KSMD protect mode for catching stale access
_ksmg_granule_locking_status	granule locking status
_ksmg_granule_size	granule size in bytes
_ksmg_lock_check_interval	timeout action interval in minutes
_ksmg_lock_reacquire_count	repeat count for acquisition of locks
_kspol_tac_timeout	timeouts for TAC registerd by kspol
_ksr_unit_test_processes	number of ksr unit test processes
_kss_quiet	if TRUE access violations during kss dumps are not recorded
_ksu_diag_kill_time	number of seconds ksuitm waits before killing diag
_ksuitm_addon_trccmd	command to execute when dead processes don’t go away
_ksuitm_dont_kill_dumper	delay inst. termination to allow processes to dump
_ksv_max_spawn_fail_limit	bg slave spawn failure limit
_ksv_pool_hang_kill_to	bg slave pool terminate timeout
_ksv_pool_wait_timeout	bg slave pool wait limit
_ksv_spawn_control_all	control all spawning of background slaves
_ksvppktmode	ksv internal pkt test
_ksxp_diagmode	set to OFF to disable automatic slowsend diagnostics
_ksxp_disable_dynamic_loading	disable dynamic loadin of lib skgxp
_ksxp_disable_ipc_stats	disable ipc statistics
_ksxp_init_stats_bkts	initial number arrays for ipc statistics
_ksxp_max_stats_bkts	max. arrays for ipc statistics
_ksxp_ping_enable	_ksxp_ping_polling_time	_ksxp_reaping	tune ksxp layer reaping limit
_ksxp_reporting_process	LMD0	reporting process for KSXP
_ksxp_send_timeout	set timeout for sends queued with the inter-instance IPC
_ksxp_skgxp_compat_library_path	over-ride default location of lib skgxp compat
_ksxp_skgxp_library_path	over-ride default location of lib skgxp
_ksxp_stats_mem_lmt	limit ipc statistics memory. this parameter is a percentage value
_ksxp_testing	KSXP test parameter
_ksxp_unit_test_byte_transformation	enable byte transformation unit test
_ktc_debug	for ktc debug
_ktc_latches	number of ktc latches
_ktslj_segext_warning	segment pre-extension warning threshold in percentage
_ktspsrch_maxsc	maximum segments supported by space search cache
_kttext_warning	tablespace pre-extension warning threshold in percentage
_ktu_latches	number of KTU latches
_ku_trace	datapump trace parameter
_large_pool_min_alloc	16000	minimum allocation size in bytes for the large allocation pool
_last_allocation_period	period over which an instance can retain an active level1 bitmap
_latch_class_0	latch class 0
_latch_class_1	latch class 1
_latch_class_2	latch class 2
_latch_class_3	latch class 3
_latch_class_4	latch class 4
_latch_class_5	latch class 5
_latch_class_6	latch class 6
_latch_class_7	latch class 7
_latch_classes	latch classes override
_latch_miss_stat_sid	Sid of process for which to collect latch stats
_latch_recovery_alignment	65534	align latch recovery structures
_ldr_io_size	size of write IOs used during a load operation
_left_nested_loops_random	enable random distribution method for left of nestedloops
_lgwr_async_broadcasts	LGWR Asynchronous broadcasts enabling boolean flag
_lgwr_delay_write	LGWR write delay for debugging
_lgwr_io_slaves	LGWR I/O slaves
_lgwr_max_ns_wt	Maximum wait time for lgwr to allow NetServer to progress
_lgwr_ns_nl_max	Variable to simulate network latency or buffer threshold
_lgwr_ns_nl_min	_lgwr_ns_sim_err	Variable to simulate errors lgwrns
_lgwr_ta_sim_err	Variable to simulate errors lgwr true async
_library_cache_advice	whether KGL advice should be turned on
_lightweight_hdrs	Lightweight headers for redo
_like_with_bind_as_equality	treat LIKE predicate with bind as an equality predicate
_lm_activate_lms_threshold	threshold value to activate an additional lms
_lm_asm_enq_hashing	if TRUE makes ASM use enqueue master hashing for fusion locks
_lm_better_ddvictim	GES better deadlock victim
_lm_cache_lvl0_cleanup	how often to cleanup level 0 cache res (in sec)
_lm_cache_res_cleanup	percentage of cached resources should be cleanup
_lm_cache_res_type	TMHWDI	cache resource: string of lock types(s)
_lm_checksum_batch_msg	GES checksum batch messages
_lm_contiguous_res_count	number of contiguous blocks that will hash to the same HV bucket
_lm_dd_interval	dd time interval in seconds
_lm_dd_max_search_time	180	max dd search time per token
_lm_dd_scan_interval	dd scan interval in seconds
_lm_dd_search_cnt	number of dd search per token get
_lm_drm_max_requests	dynamic remastering maximum affinity requests processed together
_lm_drm_window	dynamic remastering bucket window size
_lm_drm_xlatch	dynamic remastering forced exclusive latches
_lm_dynamic_lms	dynamic lms invocation
_lm_dynamic_load	dynamic load adjustment
_lm_enq_lock_freelist	Number of ges enqueue element freelist
_lm_enq_rcfg	if TRUE enables enqueue reconfiguration
_lm_enqueue_freelist	Number of enqueue freelist
_lm_file_affinity	mapping between file id and master instance number
_lm_global_posts	if TRUE deliver global posts to remote nodes
_lm_idle_connection_check	GES idle connection check
_lm_idle_connection_check_interval	GES idle connection check interval time
_lm_idle_connection_kill	GES idle connection kill
_lm_lmd_waittime	default wait time for lmd in centiseconds
_lm_lmon_Nowait_latch	if TRUE makes lmon get Nowait latches with timeout loop
_lm_lms	number of background gcs server processes to start
_lm_lms_waittime	default wait time for lms in centiseconds
_lm_locks	12000	number of enqueues configured for cluster database
_lm_master_weight	master resource weight for this instance
_lm_max_lms	max. number of background global cache server processes
_lm_msg_batch_size	GES batch message size
_lm_msg_cleanup_interval	3000	GES message buffer cleanup interval time
_lm_node_join_opt	cluster database node join optimization in reconfig
_lm_non_fault_tolerant	disable cluster database fault-tolerance mode
_lm_num_pt_buckets	number of buckets in the object affinity hash table
_lm_num_pt_latches	number of latches in the object affinity hash table
_lm_postevent_buffer_size	postevent buffer size
_lm_proc_freeze_timeout	reconfiguration: process freeze timeout
_lm_process_batching	GES implicit process batching for IPC messages
_lm_procs	320	number of client processes configured for cluster database
_lm_psrcfg	enable pseudo reconfiguration
_lm_rcfg_timeout	1260	Reconfiguration timeout
_lm_rcvr_hang_allow_time	receiver hang allow time in seconds
_lm_rcvr_hang_check_frequency	receiver hang check frequency in seconds
_lm_rcvr_hang_kill	to kill receiver hang
_lm_res_hash_bucket	number of resource hash buckets
_lm_res_part	number of resource partition configured for gcs
_lm_ress	6000	number of resources configured for cluster database
_lm_send_mode	GES send mode
_lm_send_queue_batching	GES send queue message batching
_lm_send_queue_length	GES send queue maximum length
_lm_sendproxy_reserve	GES percentage of send proxy reserve of send tickets
_lm_share_lock_opt	if TRUE enables share lock optimization
_lm_sq_batch_factor	GES send queue minimum batching factor
_lm_sq_batch_type	GES send queue batching mechanism
_lm_sq_batch_waittick	GES send queue batching waittime in tick
_lm_sync_timeout	420	Synchronization timeout for DLM reconfiguration steps
_lm_ticket_active_sendback	Flow control ticket active sendback threshold
_lm_tickets	GES messaging tickets
_lm_tx_delta	TX lock localization delta
_lm_validate_resource_type	if TRUE enables resource name validation
_lm_xids	352	number of transaction IDs configured for cluster database
_lmn_compression	suppl logging for compression enabled
_load_without_compile	NONE	Load PL/sql or Database objects without compilation
_local_communication_costing_enabled	enable local communication costing when TRUE
_local_communication_ratio	set the ratio between global and local communication (0..100)
_local_hang_analysis_interval_secs	the interval at which local hang analysis is run
_lock_sga_areas	Lock specified areas of the SGA in physical memory
_log_archive_avoid_memcpy	log archive avoid memcpy
_log_archive_buffers	Number of buffers to allocate for archiving
_log_archive_callout	archival callout
_log_archive_compress_enable	Bypass database rules for enabling archivelog compression
_log_archive_network_redo_size	Log archive network redo buffer size used by ARCH
_log_archive_prot_auto_demote	log archive protection auto demotion
_log_archive_security_enabled	log archive security enabled
_log_archive_strong_auth	log archive security strong auth
_log_blocks_during_backup	log block images when changed during backup
_log_buffers_corrupt	corrupt redo buffers before write
_log_buffers_debug	debug redo buffers (slows things down)
_log_checkpoint_recovery_check	# redo blocks to verify after checkpoint
_log_committime_block_cleanout	Log commit-time block cleanout
_log_deletion_policy	mandatory	archivelog deletion policy for mandatory/all destination
_log_event_queues	number of the log writer event queues
_log_io_size	automatically initiate log write if this many redo blocks in buffer
_log_parallelism_dynamic	Enable dynamic strands
_log_parallelism_max	Maximum number of log buffer strands
_log_private_mul	Private strand multiplier for log space preallocation
_log_private_parallelism	Number of private log buffer strands for zero-copy redo
_log_private_parallelism_mul	Active sessions multiplier to deduce number of private strands
_log_read_buffers	Number of log read buffers for media recovery
_log_simultaneous_copies	number of simultaneous copies into redo buffer(# of copy latches)
_log_space_errors	should we report space errors to alert log
_log_switch_timeout	Maximum number of seconds redos in the current log Could span
_logout_storm_rate	number of processes that can logout in a second
_logout_storm_retrycnt	maximum retry count for logouts
_logout_storm_timeout	timeout in centi-seconds for time to wait between retries
_longops_enabled	longops stats enabled
_low_server_threshold	low server thresholds
_ltc_trace	tracing level for load table conventional
_master_direct_sends	31	direct sends for messages from master (DFS)
_mav_refresh_consistent_read	refresh materialized views using consistent read snapshot
_mav_refresh_double_count_prevented	materialized view MAV refreshes avoid double counting
_mav_refresh_opt	optimizations during refresh of materialized views
_mav_refresh_unionall_tables	# tables for union all expansion during materialized view refresh
_max_arch_lns_wait	Maximum wait by ARCH to allow NetServer to complete archival
_max_exponential_sleep	max sleep during exponential backoff
_max_io_size	Maximum I/O size in bytes for sequential file accesses
_max_large_io	IORM:max number of large I/O’s to issue
_max_lns_shutdown_archival_time	Maximum time spent by LNS to archive last log during shutdown
_max_protocol_support	Max occurrence protocols supported in a process
_max_shrink_obj_stats	number of segments for which shrink stats will be maintained
_max_sleep_holding_latch	max time to sleep while holding a latch
_max_small_io	IORM:max number of small I/O’s to issue
_max_spacebg_slaves	maximum space management background slaves
_max_spacebg_tasks	maximum space management background tasks
_max_temp_overhead	max tempspc overhead
_media_recovery_read_batch	media recovery block read batch
_mem_annotation_pr_lev	private memory annotation collection level
_mem_annotation_scale	memory annotation pre-allocation scaling
_mem_annotation_sh_lev	shared memory annotation collection level
_mem_annotation_store	memory annotation in-memory store
_mem_std_extent_size	standard extent size for fixed-size-extent heaps
_memory_broker_log_stat_entries	memory broker num stat entries
_memory_broker_marginal_utility_bc	12	Marginal Utility threshold pct for bc
_memory_broker_marginal_utility_sp	Marginal Utility threshold pct for sp
_memory_broker_shrink_heaps	memory broker allow policy to shrink shared pool
_memory_broker_shrink_java_heaps	memory broker allow policy to shrink java pool
_memory_broker_shrink_streams_pool	memory broker allow policy to shrink streams pool
_memory_broker_shrink_timeout	60000000	memory broker policy to timeout shrink shared/java pool
_memory_broker_stat_interval	memory broker statistics gathering interval for auto sga
_memory_management_tracing	trace memory management activity
_memory_nocancel_defsgareq	do not cancel deferred sga reqs with auto-memory
_memory_sanity_check	partial granule sanity check
_messages	message queue resources – dependent on # processes & # buffers
_midtier_affinity_clusterwait_threshold	cluster wait threshold to enter affinity
_midtier_affinity_goodness_threshold	goodness gradient threshold to dissolve affinity
_midtier_affinity_timeout	default timeout for midtier affinity processing
_minfree_plus	max percentage of block space + minfree before we mark block full
_minimal_stats_aggregation	prohibit stats aggregation at compile/partition maintenance time
_minimum_blocks_to_shrink	minimum number freeable blocks for shrink to be present
_minimum_db_flashback_retention	Minimum flashback retention
_minimum_extents_to_shrink	minimum number freeable extents for shrink to be present
_minimum_giga_scn	Minimum SCN to start with in 2^30 units
_mirror_redo_buffers	Save buffers for debugging redo corruptions
_mmv_query_rewrite_enabled	allow rewrites with multiple MVs and/or base tables
_multi_instance_pmr	force multi instance or single instance parallel recovery
_multi_join_key_table_lookup	TRUE iff multi-join-key table lookup prefetch is enabled
_multiple_instance_recovery	use multiple instances for media recovery
_mv_refresh_ana	what percent to analyze after complete/PCT refresh
_mv_refresh_costing	rule	refresh decision based on cost or on rules
_mv_refresh_delta_fraction	delta mv as fractional percentage of size of mv
_mv_refresh_eut	refresh materialized views using EUT(partition)-based algorithm
_mv_refresh_force_parallel_query	force materialized view refreshes to use parallel query
_mv_refresh_new_setup_disabled	materialized view MV refresh new setup disabling
_mv_refresh_rebuild_percentage	minimum percentage change required in MV to force an indexrebuild
_mv_refresh_selections	create materialized views with selections and fast refresh
_mv_refresh_use_stats	pass cardinality hints to refresh queries
_mv_refsched_timeincr	300000	proportionality constant for dop vs. time in MV refresh
_mv_rolling_inv	create/alter mv uses rolling cursor invalidation instead of immediate
_mwin_schedule	Enable/disable Maintenance Window Schedules
_nchar_imp_cnv	NLS allow Implicit Conversion between CHAR and NCHAR
_nchar_imp_conv	should implicit conversion bewteen clob and nclob be allowed
_ncmb_readahead_enabled	enable multi-block readahead for an index scan
_ncmb_readahead_tracing	turn on multi-block readahead tracing
_ncomp_shared_objects_dir	native compilation shared objects dir
_nested_loop_fudge	nested loop fudge
_nested_mav_fast_oncommit_enabled	nested MAV refresh fast on commit allowed
_new_initial_join_orders	enable initial join orders based on new ordering heuristics
_new_sort_cost_estimate	enables the use of new cost estimate for sort
_newsort_enabled	controls whether new sorts can be used as system sort
_newsort_ordered_pct	63	controls when new sort avoids sorting ordered input
_newsort_type	specifies options for the new sort algorithm
_nlj_batching_enabled	enable batching of the RHS IO in NLJ
_nlj_batching_misses_enabled	enable exceptions for buffer cache misses
_no_objects	no object features are used
_no_or_expansion	OR expansion during optimization disabled
_no_recovery_through_resetlogs	no recovery through this resetlogs operation
_notify_crs	notify cluster ready services of startup and shutdown
_ns_max_flush_wt	Flush wait time for NetServer to flush oustanding writes
_ns_max_send_delay	Data Loss Time Bound for NetServer
_num_longop_child_latches	number of child latches for long op array
_number_cached_attributes	maximum number of cached attributes per instance
_object_reuse_bast	if 1 or higher,handle object reuse
_object_statistics	enable the object level statistics collection
_object_stats_max_entries	3072	Maximum number of entries to be tracked per stat
_offline_rollback_segments	offline undo segment list
_ogms_home	GMS home directory
_olap_aggregate_buffer_size	OLAP Aggregate max buffer size
_olap_aggregate_flags	OLAP Aggregate debug flags
_olap_aggregate_function_cache_enabled	OLAP Aggregate function cache enabler
_olap_aggregate_function_merge_threshold	529	OLAP Aggregate function merge threshold
_olap_aggregate_max_thread_tuples	OLAP Aggregate max thread tuples creation
_olap_aggregate_min_buffer_size	OLAP Aggregate min buffer size
_olap_aggregate_min_thread_status	OLAP Aggregate minimum cardinality of dimensions for thread
_olap_aggregate_multipath_hier	OLAP Aggregate Multi-path Hierarhies enabled
_olap_aggregate_statlen_thresh	OLAP Aggregate status array usage threshold
_olap_aggregate_store_probability	OLAP Aggregate function storeback probability
_olap_aggregate_work_per_thread	OLAP Aggregate max work parents
_olap_aggregate_worklist_max	OLAP Aggregate max worklists generated at once
_olap_allocate_errorlog_format	%8p %8y %8z %e (%n)	OLAP Allocate Errorlog Format
_olap_allocate_errorlog_header	Dim Source Basis %-8d %-8s %-8b Description ——– ——– ——– ———–	OLAP Allocate Errorlog Header format
_olap_analyze_max	OLAP DML ANALYZE command max cells to analyze
_olap_continuous_trace_file	Specify TRUE to enable continuous OLAP tracing – otherwise only exceptional events will be logged
_olap_dbgoutfile_echo_to_eventlog	OLAP DbgOutfile copy output to event log (tracefile)
_olap_dimension_corehash_class	OLAP Dimension In-Core Hash Table Class
_olap_dimension_corehash_large	50000	OLAP Dimension In-Core Hash Table Large Threshold
_olap_dimension_corehash_pressure	OLAP Dimension In-Core Hash Table Pressure Threshold
_olap_dimension_corehash_size	OLAP Dimension In-Core Hash Table Maximum Memory Use
_olap_dimension_corehash_small	OLAP Dimension In-Core Hash Table Small Threshold
_olap_eif_export_lob_size	2147483647	OLAP EIF Export BLOB size
_olap_lmgen_dim_size	Limitmap generator dimension column size
_olap_lmgen_meas_size	Limitmap generator measure column size
_olap_object_hash_class	OLAP Object Hash Table Class
_olap_page_pool_expand_rate	OLAP Page Pool Expand Rate
_olap_page_pool_hi	OLAP Page Pool High Watermark
_olap_page_pool_hit_target	OLAP Page Pool Hit Target
_olap_page_pool_low	OLAP Page Pool Low Watermark
_olap_page_pool_pressure	OLAP Page Pool Pressure Threshold
_olap_page_pool_shrink_rate	OLAP Page Pool Shrink Rate
_olap_parallel_update_small_group	OLAP parallel update pagespace by group
_olap_parallel_update_small_threshold	OLAP parallel update threshold for number of small pagespaces
_olap_parallel_update_threshold	OLAP parallel update threshold in pages
_olap_poutlog_echo_to_eventlog	OLAP POutLog copy output to event log (tracefile)
_olap_sesscache_enabled	OLAP Session Cache knob
_olap_sort_buffer_size	OLAP Sort Buffer Size
_olap_statbool_corebits	20000000	OLAP Status Boolean max incore bits
_olap_statbool_threshold	8100	OLAP Status Boolean CBM threshold
_olap_table_function_statistics	Specify TRUE to output OLAP table function timed statistics trace
_olap_wrap_errors	Wrap error messages to OLAP outfile
_olapi_history_retention	enable olapi history retention
_olapi_iface_object_history	enable olapi interface object history collection
_olapi_iface_object_history_retention	enable olapi interface object history retention
_olapi_iface_operation_history_retention	enable olapi interface operation history retention
_olapi_interface_operation_history	enable olapi interface operation history collection
_olapi_memory_operation_history	enable olapi memory alloc/free history collection
_olapi_memory_operation_history_pause_at_seqno	enable olapi memory alloc/free history collection pausing
_olapi_memory_operation_history_retention	enable olapi memory operation history retention
_olapi_session_history	enable olapi session history collection
_olapi_session_history_retention	enable olapi session history retention
_old_connect_by_enabled	enable/disable old connect by
_ols_cleanup_task	Clean up unnecessary entries in OLS sessinfo table
_oltp_compression	oltp compression enabled
_oltp_compression_gain	oltp compression gain
_omf	enabled	enable/disable OMF
_oneside_colstat_for_equijoins	_online_patch_disable_stack_check	disable check for function on stack for online patches
_optim_adjust_for_part_skews	adjust stats for skews across partitions
_optim_dict_stats_at_db_cr_upg	enable/disable dictionary stats gathering at db create/upgrade
_optim_enhance_nnull_detection	TRUE to enable index [fast] full scan more often
_optim_new_default_join_sel	improves the way default equijoin selectivity are computed
_optim_peek_user_binds	enable peeking of user binds
_optimizer_adaptive_cursor_sharing	optimizer adaptive cursor sharing
_optimizer_adjust_for_nulls	adjust selectivity for null values
_optimizer_autostats_job	enable/disable auto stats collection job
_optimizer_aw_join_push_enabled	Enables AW Join Push optimization
_optimizer_aw_stats_enabled	Enables statistcs on AW olap_table table function
_optimizer_better_inlist_costing	ALL	enable improved costing of index access using in-list(s)
_optimizer_block_size	standard block size used by optimizer
_optimizer_cache_stats	cost with cache statistics
_optimizer_cartesian_enabled	optimizer cartesian join enabled
_optimizer_cbqt_factor	cost factor for cost-based query transformation
_optimizer_cbqt_no_size_restriction	disable cost based transformation query size restriction
_optimizer_ceil_cost	CEIL cost in CBO
_optimizer_choose_permutation	force the optimizer to use the specified permutation
_optimizer_complex_pred_selectivity	enable selectivity estimation for builtin functions
_optimizer_compute_index_stats	force index stats collection on index creation/rebuild
_optimizer_connect_by_combine_sw	combine no filtering connect by and start with
_optimizer_connect_by_cost_based	use cost-based transformation for connect by
_optimizer_correct_sq_selectivity	force correct computation of subquery selectivity
_optimizer_cost_based_transformation	LINEAR	enables cost-based query transformation
_optimizer_cost_filter_pred	enables costing of filter predicates in IO cost model
_optimizer_cost_hjsmj_multimatch	add cost of generating result set when #rows per key > 1
_optimizer_cost_model	optimizer cost model
_optimizer_degree	force the optimizer to use the same degree of parallelism
_optimizer_dim_subq_join_sel	use join selectivity in choosing star transformation dimensions
_optimizer_disable_strans_sanity_checks	disable star transformation sanity checks
_optimizer_distinct_elimination	Eliminates redundant SELECT disTNCT’s
_optimizer_dyn_smp_blks	number of blocks for optimizer dynamic sampling
_optimizer_enable_density_improvements	use improved density computation for selectivity estimation
_optimizer_enable_extended_stats	use extended statistics for selectivity estimation
_optimizer_enhanced_filter_push	push filters before trying cost-based query transformation
_optimizer_extend_jppd_view_types	join pred pushdown on group-by,distinct,semi-/anti-joined view
_optimizer_extended_cursor_sharing	UDO	optimizer extended cursor sharing
_optimizer_extended_cursor_sharing_rel	SIMPLE	optimizer extended cursor sharing for relational operators
_optimizer_extended_stats_usage_control	240	controls the optimizer usage of extended stats
_optimizer_filter_pred_pullup	use cost-based flter predicate pull up transformation
_optimizer_fkr_index_cost_bias	Optimizer index bias over FTS/IFFS under first K rows mode
_optimizer_free_transformation_heap	free transformation subheap after each transformation
_optimizer_group_by_placement	consider group-by placement optimization
_optimizer_ignore_hints	enables the embedded hints to be ignored
_optimizer_improve_selectivity	improve table and partial overlap join selectivity computation
_optimizer_invalidation_period	18000	time window for invalidation of cursors of analyzed objects
_optimizer_join_elimination_enabled	optimizer join elimination enabled
_optimizer_join_order_control	controls the optimizer join order search algorithm
_optimizer_join_sel_sanity_check	enable/disable sanity check for multi-column join selectivity
_optimizer_max_permutations	optimizer maximum join permutations per query block
_optimizer_min_cache_blocks	set minimum cached blocks
_optimizer_mjc_enabled	enable merge join cartesian
_optimizer_mode_force	force setting of optimizer mode for user recursive sql also
_optimizer_multi_level_push_pred	consider join-predicate pushdown that requires multi-level pushdown to base table
_optimizer_multiple_cenv	generate and run plans using several compilation environments
_optimizer_native_full_outer_join	FORCE	execute full outer join using native implementaion
_optimizer_nested_rollup_for_gset	number of groups above which we use nested rollup exec for gset
_optimizer_new_join_card_computation	compute join cardinality using non-rounded input values
_optimizer_null_aware_antijoin	null-aware antijoin parameter
_optimizer_or_expansion	DEPTH	control or expansion approach used
_optimizer_or_expansion_subheap	Use subheap for optimizer or-expansion
_optimizer_order_by_elimination_enabled	Eliminates order bys from views before query transformation
_optimizer_outer_to_anti_enabled	Enable transformation of outer-join to anti-join if possible
_optimizer_percent_parallel	101	optimizer percent parallel
_optimizer_push_down_distinct	push down distinct from query block to table
_optimizer_push_pred_cost_based	use cost-based query transformation for push pred optimization
_optimizer_random_plan	optimizer seed value for random plans
_optimizer_reuse_cost_annotations	reuse cost annotations during cost-based query transformation
_optimizer_rownum_bind_default	Default value to use for rownum bind
_optimizer_rownum_pred_based_fkr	enable the use of first K rows due to rownum predicate
_optimizer_save_stats	enable/disable saving old versions of optimizer stats
_optimizer_search_limit	optimizer search limit
_optimizer_self_induced_cache_cost	account for self-induced caching
_optimizer_skip_scan_enabled	enable/disable index skip scan
_optimizer_skip_scan_guess	consider index skip scan for predicates with guessed selectivity
_optimizer_sortmerge_join_enabled	enable/disable sort-merge join method
_optimizer_sortmerge_join_inequality	enable/disable sort-merge join using inequality predicates
_optimizer_squ_bottomup	enables unnesting of subquery in a bottom-up manner
_optimizer_star_tran_in_with_clause	enable/disable star transformation in with clause queries
_optimizer_star_trans_min_cost	optimizer star transformation minimum cost
_optimizer_star_trans_min_ratio	optimizer star transformation minimum ratio
_optimizer_starplan_enabled	optimizer star plan enabled
_optimizer_system_stats_usage	system statistics usage
_optimizer_trace	optimizer trace parameter
_optimizer_transitivity_retain	retain equi-join pred upon transitive equality pred generation
_optimizer_undo_changes	undo changes to query optimizer
_optimizer_undo_cost_change	11.1.0.6	optimizer undo cost change
_optimizer_use_subheap	Enables physical optimizer subheap
_or_expand_nvl_predicate	enable OR expanded plan for NVL/DECODE predicate
_oradbg_pathname	path of oradbg script
_oradebug_force	force target processes to execute oradebug commands?
_ordered_nested_loop	enable ordered nested loop costing
_ordered_semijoin	enable ordered semi-join subquery
_orph_cln_interval	1200	qmon periodic interval for removed subscriber messages cleanup
_os_sched_high_priority	OS high priority level
_other_wait_event_exclusion	exclude event names from _other_wait_threshold calculations
_other_wait_threshold	threshold wait percentage for event wait class Other
_outline_bitmap_tree	BITMAP_TREE hint enabled in outline
_parallel_adaptive_max_users	maximum number of users running with default DOP
_parallel_broadcast_enabled	enable broadcasting of small inputs to hash and sort merge joins
_parallel_default_max_instances	default maximum number of instances for parallel query
_parallel_execution_message_align	Alignment of PX buffers to OS page boundary
_parallel_fake_class_pct	fake db-scheduler percent used for testing
_parallel_fixwrite_bucket	Number of buckets for each round of fix write
_parallel_load_bal_unit	number of threads to allocate per instance
_parallel_load_balancing	parallel execution load balanced slave allocation
_parallel_min_message_pool	206592	minimum size of shared pool memory to reserve for pq servers
_parallel_policy	MANUAL	policy used to compute the degree of parallelism (MANUAL/LIMITED/AUTO)
_parallel_recovery_stopat	32767	stop at -position- to step through SMON
_parallel_replay_msg_limit	4000	Number of messages for each round of parallel replay
_parallel_server_idle_time	idle time before parallel query server dies (in 1/100 sec)
_parallel_server_sleep_time	sleep time between dequeue timeouts (in 1/100ths)
_parallel_slave_acquisition_wait	time(in seconds) to wait before retrying slave acquisition
_parallel_time_threshold	threshold above which a plan is a candidate for parallelization (in seconds)
_parallel_time_unit	unit of work used to derive the degree of parallelism (in seconds)
_parallel_txn_global	enable parallel_txn hint with updates and deletes
_parallelism_cost_fudge_factor	350	set the parallelism cost fudge factor
_parameter_table_block_size	parameter table block size
_partial_pwise_join_enabled	enable partial partition-wise join when TRUE
_partition_view_enabled	enable/disable partitioned views
_passwordfile_enqueue_timeout	password file enqueue timeout in seconds
_pct_refresh_double_count_prevented	materialized view PCT refreshes avoid double counting
_pdml_gim_sampling	control separation of global index maintenance for PDML
_pdml_gim_staggered	slaves start on different index when doing index maint
_pdml_slaves_diff_part	slaves start on different partition when doing index maint
_percent_flashback_buf_partial_full	Percent of flashback buffer filled to be considered partial full
_pga_large_extent_size	PGA large extent size
_pga_max_size	Maximum size of the PGA memory for one process
_ping_level	fusion ping level
_pivot_implementation_method	pivot implementation method
_pkt_enable	enable progressive kill test
_pkt_pmon_interval	PMON process clean-up interval (cs)
_pkt_start	start progressive kill test instrumention
_plan_outline_data	explain plan outline data enabled
_plan_verify_improvement_margin	150	Performance improvement criterion for evolving plan baselines
_plan_verify_local_time_limit	Local time limit to use for an individual plan verification
_plsql_anon_block_code_type	INTERPRETED	PL/sql anonymous block code-type
_plsql_cache_enable	PL/sql Function Cache Enabled
_plsql_dump_buffer_events	conditions upon which the PL/sql circular buffer is dumped
_plsql_minimum_cache_hit_percent	plsql minimum cache hit percentage required to keep caching active
_plsql_nvl_optimize	PL/sql NVL optimize
_pmon_load_constants	300,192,64,3,10,0	server load balancing constants (S,P,D,I,L,C,M)
_pre_rewrite_push_pred	push predicates into views before rewrite
_precompute_gid_values	precompute gid values and copy them before returning a row
_pred_move_around	enables predicate move-around
_predicate_elimination_enabled	allow predicate elimination if set to TRUE
_prescomm	presume commit of IMU transactions
_print_refresh_schedule	false	enable dbms_output of materialized view refresh schedule
_private_memory_address	Start address of large extent memory segment
_project_view_columns	enable projecting out unreferenced columns of a view
_projection_pushdown	projection pushdown
_projection_pushdown_debug	level for projection pushdown debugging
_prop_old_enabled	Shift to pre 11g propagation behavIoUr
_protect_frame_heaps	Protect cursor frame heaps
_push_join_predicate	enable pushing join predicate inside a view
_push_join_union_view	enable pushing join predicate inside a union all view
_push_join_union_view2	enable pushing join predicate inside a union view
_px_async_getgranule	asynchronous get granule in the slave
_px_bind_peek_sharing	enables sharing of px cursors that were built using bind peeking
_px_broadcast_fudge_factor	set the tq broadcasting fudge factor percentage
_px_buffer_ttl	ttl for px mesg buffers in seconds
_px_compilation_debug	debug level for parallel compilation
_px_compilation_trace	tracing level for parallel compilation
_px_dump_12805_source	enables or disables tracing of 12805 signal source
_px_dynamic_opt	turn off/on restartable qerpx dynamic optimization
_px_dynamic_sample_size	num of samples for restartable qerpx dynamic optimization
_px_execution_services_enabled	enable service-based constraint of px slave allocation
_px_granule_size	100000	default size of a rowid range granule (in KB)
_px_index_sampling	parallel query sampling for index create (100000 = 100%)
_px_io_process_bandwidth	IO process bandwidth in MB/sec for computing DOP
_px_io_system_bandwidth	total IO system bandwidth in MB/sec for computing DOP
_px_kxib_tracing	turn on kxib tracing
_px_load_publish_interval	interval at which LMON will check whether to publish PX load
_px_loc_msg_cost	cpu cost to send a PX message via shared memory
_px_max_granules_per_slave	maximum number of rowid range granules to generate per slave
_px_min_granules_per_slave	13	minimum number of rowid range granules to generate per slave
_px_minus_intersect	enables pq for minus/interect operators
_px_net_msg_cost	cpu cost to send a PX message over the internconnect
_px_no_granule_sort	prevent parallel partition granules to be sorted on size
_px_no_stealing	prevent parallel granule stealing in shared nothing environment
_px_nss_planb	enables or disables NSS Plan B reparse with outline
_px_proc_constrain	reduce parallel_max_servers if greater than (processes – fudge)
_px_pwg_enabled	parallel partition wise group by enabled
_px_rownum_pd	turn off/on parallel rownum pushdown optimization
_px_send_timeout	IPC message send timeout value in seconds
_px_slaves_share_cursors	slaves share cursors with QC
_px_trace	px trace parameter
_px_ual_serial_input	enables new pq for UNION operators
_px_xtgranule_size	default size of a external table granule (in KB)
_qa_control	Oracle internal parameter to control QA
_qa_lrg_type	Oracle internal parameter to specify QA lrg type
_query_cost_rewrite	perform the cost based rewrite with materialized views
_query_execution_cache_max_size	max size of query execution cache
_query_mmvrewrite_maxcmaps	query mmv rewrite maximum number of cmaps per dmap in query disjunct
_query_mmvrewrite_maxdmaps	query mmv rewrite maximum number of dmaps per query disjunct
_query_mmvrewrite_maxinlists	query mmv rewrite maximum number of in-lists per disjunct
_query_mmvrewrite_maxintervals	query mmv rewrite maximum number of intervals per disjunct
_query_mmvrewrite_maxmergedcmaps	query mmv rewrite maximum number of merged cmaps
_query_mmvrewrite_maxpreds	query mmv rewrite maximum number of predicates per disjunct
_query_mmvrewrite_maxqryinlistvals	query mmv rewrite maximum number of query in-list values
_query_mmvrewrite_maxregperm	512	query mmv rewrite maximum number of region permutations
_query_rewrite_1	perform query rewrite before&after or only before view merging
_query_rewrite_2	perform query rewrite before&after or only after view merging
_query_rewrite_drj	mv rewrite and drop redundant joins
_query_rewrite_expression	rewrite with cannonical form for expressions
_query_rewrite_fpc	mv rewrite fresh partition containment
_query_rewrite_fudge	cost based query rewrite with MVs fudge factor
_query_rewrite_jgmigrate	mv rewrite with jg migration
_query_rewrite_maxdisjunct	257	query rewrite max disjuncts
_query_rewrite_or_error	allow query rewrite,if referenced tables are not dataless
_query_rewrite_setopgrw_enable	perform general rewrite using set operator summaries
_query_rewrite_vop_cleanup	prune frocol chain before rewrite after view-merging
_rcfg_parallel_fixwrite	if TRUE enables parallel fixwrite at reconfiguration
_rcfg_parallel_replay	if TRUE enables parallel replay and cleanup at reconfiguration
_rcfg_parallel_verify	if TRUE enables parallel verify at reconfiguration
_rdbms_compatibility	default RDBMS compatibility level
_rdbms_internal_fplib_enabled	enable SAGE FPLIB filtering within rdbms
_rdbms_internal_fplib_raise_errors	enable reraising of any exceptions in SAGE FPLIB
_readable_standby_mode	SLFLUSH	readable standby mode
_readable_standby_sync_timeout	readable standby query scn sync timeout
_real_time_apply_sim	Simulation value with real time apply
_realfree_heap_max_size	minimum max total heap size,in Kbytes
_realfree_heap_mode	mode flags for real-free heap
_realfree_heap_pagesize_hint	hint for real-free page size in bytes
_recoverable_recovery_batch_percent	Recoverable recovery batch size (percentage of buffer cache)
_recovery_asserts		_recovery_percentage	recovery buffer cache percentage
_recovery_verify_writes	enable thread recovery write verify
_recursive_imu_transactions	recursive transactions may be IMU
_redo_compatibility_check	general and redo/undo compatibility sanity check
_redo_read_from_memory	Enable reading redo from memory
_redo_transport_compress_all	Is ASYNC LNS compression allowed?
_release_insert_threshold	maximum number of unusable blocks to unlink from freelist
_reliable_block_sends		_remove_aggr_subquery	enables removal of subsumed aggregated subquery
_replace_virtual_columns	replace expressions with virtual columns
_resource_manager_always_off	disable the resource manager always
_resource_manager_always_on	enable the resource manager always
_restore_spfile	restore spfile to this location
_result_cache_auto_execution_threshold	result cache auto execution threshold
_result_cache_auto_size_threshold	result cache auto max size allowed
_result_cache_auto_time_distance	result cache auto time distance
_result_cache_auto_time_threshold	result cache auto time threshold
_result_cache_block_size	result cache block size
_result_cache_timeout	maximum time (sec) a session waits for a result
_reuse_index_loop	number of blocks being examine for index block reuse
_right_outer_hash_enable	Right Outer/Semi/Anti Hash Enabled
_rman_io_priority	priority at which rman backup I/O’s are done
_rman_restore_through_link	RMAN restore through link
_rollback_segment_count	number of undo segments
_rollback_segment_initial	starting undo segment number
_rollback_stopat	stop at -position to step rollback
_row_cache_cursors	number of cached cursors for row cache management
_row_cr	enable row cr for all sql
_row_locking	always	row-locking
_row_shipping_explain	enable row shipping explain plan support
_row_shipping_threshold	80	row shipping column selection threshold
_rowsource_execution_statistics		_rowsource_profiling_statistics		_rowsource_statistics_sampfreq	frequency of rowsource statistic sampling (must be a power of 2)
_rowsrc_trace_level	Row source tree tracing level
_rtc_infeasible_threshold	Redo Transport Compression infeasible threshold
_sage_enabled	enable real SAGE functionality
_sage_fcre	Allow optimized file creation path for SAGE
_sample_rows_per_block	number of rows per block used for sampling IO optimization
_scatter_gcs_resources	rmly across sub pools
_scatter_gcs_shadows	rmly across sub pools
_scn_wait_interface_max_backoff_time_secs	max exponential backoff time for scn wait interface in kta
_scn_wait_interface_max_timeout_secs	max timeout for scn wait interface in kta
_sdiag_crash	sql diag crash
_sec_enable_test_rpcs	Whether to enable the test RPCs
_second_spare_parameter	second spare parameter – integer
_securefile_timers	collect kdlu timers and accumulate per layers
_selectivity_for_srf_enabled	enable/disable selectivity for storage reduction factor
_selfjoin_mv_duplicates	control rewrite self-join algorithm
_selftune_checkpoint_write_pct	Percentage of total physical I/Os for self-tune ckpt
_selftune_checkpointing_lag	Self-tune checkpointing lag the tail of the redo log
_send_ast_to_foreground		_send_close_with_block		_send_requests_to_pi		_serial_direct_read	enable direct read in serial
_serial_recovery	force serial recovery or parallel recovery
_serializable	serializable
_session_cached_instantiations	Number of pl/sql instantiations to cache in a session.
_session_context_size	session app context size
_session_idle_bit_latches	one latch per session or a latch per group of sessions
_session_idle_check_interval	Resource Manager session idle limit check interval in seconds
_session_kept_cursor_pins	Number of cursors pins to keep in a session
_session_wait_history	enable session wait history collection
_seventh_spare_parameter	seventh spare parameter – string list
_sga_clear_dump	Allow dumping encrypted blocks in clear for debugging
_sga_early_trace	sga early trace event
_sga_locking	sga granule locking state
_shared_io_pool_buf_size	Shared IO pool buffer size
_shared_io_pool_debug_trc	trace kcbi debug info to tracefile
_shared_io_pool_size	Size of shared IO pool
_shared_io_set_value	shared io pool size set internal value – overwrite zero user size
_shared_iop_max_size	536870912	maximum shared io pool size
_shared_pool_max_size	shared pool maximum size when auto SGA enabled
_shared_pool_minsize_on	shared pool minimum size when auto SGA enabled
_shared_pool_reserved_min_alloc	4400	minimum allocation size in bytes for reserved area of shared pool
_shared_pool_reserved_pct	percentage memory of the shared pool allocated for the reserved area
_shared_server_load_balance	shared server load balance
_shared_server_num_queues	number of shared server common queues
_short_stack_timeout_ms	short stack timeout in ms
_shrunk_aggs_disable_threshold	percentage of exceptions at which to switch to full length aggs
_shrunk_aggs_enabled	enable use of variable sized buffers for non-distinct aggregates
_side_channel_batch_size	number of messages to batch in a side channel message (DFS)
_side_channel_batch_timeout	timeout before shipping out the batched side channelmessages in seconds
_side_channel_batch_timeout_ms	timeout before shipping out the batched side channelmessages in milliseconds
_simple_view_merging	control simple view merging performed by the optimizer
_simulate_mem_transfer	simulate auto memory sga/pga transfers
_simulator_bucket_mindelta	LRU bucket minimum delta
_simulator_internal_bound	simulator internal bound percent
_simulator_lru_rebalance_sizthr	LRU list rebalance threshold (size)
_simulator_lru_rebalance_thresh	10240	LRU list rebalance threshold (count)
_simulator_lru_scan_count	LRU scan count
_simulator_pin_inval_maxcnt	maximum count of invalid chunks on pin list
_simulator_reserved_heap_count	simulator reserved heap count
_simulator_reserved_obj_count	simulator reserved object count
_simulator_sampling_factor	sampling factor for the simulator
_simulator_upper_bound_multiple	upper bound multiple of pool size
_single_process	run without detached processes
_siop_flashback_scandepth	Shared IO pool flashback io completion scan depth
_sixth_spare_parameter	sixth spare parameter – string list
_skgxp_reaping	tune skgxp OSD reaping limit
_skgxp_udp_ach_reaping_time	time in minutes before idle ach’s are reaped
_skgxp_udp_ack_delay	Enables delayed acks
_skgxp_udp_enable_dynamic_credit_mgmt	Enables dynamic credit management
_skgxp_udp_hiwat_warn	ach hiwat mark warning interval
_skgxp_udp_interface_detection_time_secs	time in seconds between interface detection checks
_skgxp_udp_keep_alive_ping_timer_secs	connection idle time in seconds before keep alive is initiated. min: 30 sec max: 1800 sec default: 300 sec
_skgxp_udp_lmp_mtusize	MTU size for UDP LMP testing
_skgxp_udp_lmp_on	enable UDP long message protection
_skgxp_udp_timed_wait_buffering	diagnostic log buffering space (in bytes) for timed wait (0 means unbufferd
_skgxp_udp_timed_wait_seconds	time in seconds before timed wait is invoked
_skgxp_udp_use_tcb	disable use of high speek timer
_skip_assume_msg		_slave_mapping_enabled	enable slave mapping when TRUE
_slave_mapping_group_size	force the number of slave group in a slave mapper
_small_table_threshold	541	threshold level of table size for direct reads
_smm_advice_enabled		_smm_advice_log_size	overwrites default size of the PGA advice workarea history log
_smm_auto_cost_enabled		_smm_auto_max_io_size	248	Maximum IO size (in KB) used by sort/hash-join in auto mode
_smm_auto_min_io_size	56	Minimum IO size (in KB) used by sort/hash-join in auto mode
_smm_bound	overwrites memory manager automatically computed bound
_smm_control	provides controls on the memory manager
_smm_freeable_retain	5120	value in KB of the instance freeable PGA memory to retain
_smm_isort_cap	102400	maximum work area for insertion sort(v1)
_smm_max_size	40960	maximum work area size in auto mode (serial)
_smm_min_size	204	minimum work area size in auto mode
_smm_px_max_size	maximum work area size in auto mode (global)
_smm_retain_size	work area retain size in SGA for shared server sessions (0 for AUTO)
_smm_trace	Turn on/off tracing for sql memory manager
_smon_internal_errlimit	limit of SMON internal errors
_smon_undo_seg_rescan_limit	limit of SMON continous undo segments re-scan
_smu_debug_mode	- set debug event for testing SMU operations
_smu_error_simulation_site	site ID of error simulation in KTU code
_smu_error_simulation_type	error type for error simulation in KTU code
_smu_timeouts	comma-separated *AND double-quoted* list of AUM timeouts: mql,tur,sess_exprn,qry_exprn,slot_intvl
_sort_elimination_cost_ratio	cost ratio for sort eimination under first_rows mode
_sort_multiblock_read_count	multi-block read count for sort
_space_align_size	space align size
_spin_count	Amount to spin waiting for a latch
_spr_max_rules	maximum number of rules in sql spreadsheet
_spr_push_pred_refspr	push predicates through reference spreadsheet
_spr_use_AW_AS	enable AW for hash table in spreadsheet
_spr_use_hash_table	use hash table for spreadsheet
_sql_analyze_parse_model	sql Analyze Parse Model control parameter
_sql_connect_capability_override	sql Connect Capability Table Override
_sql_connect_capability_table	sql Connect Capability Table (testing only)
_sql_hash_debug	Hash value of the sql statement to debug
_sql_model_unfold_forloops	RUN_TIME	specifies compile-time unfolding of sql model forloops
_sql_plan_baseline_capture_on_1_exec	With auto-capture on,create new sql plan baseline on first exec
_sqlexec_progression_cost	sql execution progression monitoring cost threshold
_sqlmon_max_plan	Maximum number of plans entry that can be monitored. Defaults to 20 per cpu
_sqlmon_max_planlines	Number of plan lines beyond which a plan cannot be monitored
_sqlmon_threshold	cpu/IO time threshold before a statement is monitored. 0 is disabled
_sqltune_category_parsed	DEFAULT	Parsed category qualifier for applying hintsets
_srvntfn_job_deq_timeout	srvntfn job deq timeout
_srvntfn_jobsubmit_interval	srvntfn job submit interval
_srvntfn_max_concurrent_jobs	srvntfn max concurrent jobs
_srvntfn_q_msgcount	srvntfn q msg count for job exit
_srvntfn_q_msgcount_inc	srvntfn q msg count increase for job submit
_sscr_dir	Session State Capture and Restore DIRectory object
_sscr_osdir	Session State Capture and Restore OS DIRectory
_sta_control	sql Tuning Advisory control parameter
_stack_guard_level	stack guard level
_static_backgrounds	static backgrounds
_statistics_based_srf_enabled	enable/disable the use of statistics for storage reduction factor
_step_down_limit_in_pct	step down limit in percentage
_stn_trace	sql tracing parameter
_storage_predicate_access_predicate	put storage predicate into access predicate in explain plan
_streams_pool_max_size	streams pool maximum size when auto SGA enabled
_subquery_pruning_cost_factor	subquery pruning cost factor
_subquery_pruning_enabled	enable the use of subquery predicates to perform pruning
_subquery_pruning_mv_enabled	enable the use of subquery predicates with MVs to perform pruning
_subquery_pruning_reduction	subquery pruning reduction factor
_swrf_metric_frequent_mode	Enable/disable SWRF Metric Frequent Mode Collection
_swrf_mmon_dbfus	Enable/disable SWRF MMON DB Feature Usage
_swrf_mmon_flush	Enable/disable SWRF MMON FLushing
_swrf_mmon_metrics	Enable/disable SWRF MMON Metrics Collection
_swrf_on_disk_enabled	Parameter to enable/disable SWRF
_swrf_test_action	test action parameter for SWRF
_swrf_test_dbfus	Enable/disable DB Feature Usage Testing
_synonym_repoint_tracing	whether to trace Metadata comparisons for synonym repointing
_sysaux_test_param	test parameter for SYSAUX
_system_index_caching	optimizer percent system index caching
_system_trig_enabled	are system triggers enabled
_ta_lns_wait_for_arch_log	LNS Wait time for arhcived version of online log
_table_lookup_prefetch_size	table lookup prefetch vector size
_table_lookup_prefetch_thresh	table lookup prefetch threshold
_table_scan_cost_plus_one	bump estimated full table scan and index ffs cost by one
_target_rba_max_lag_percentage	target rba max log lag percentage
_tdb_debug_mode	set debug mode for testing transportable database
_temp_tran_block_threshold	number of blocks for a dimension before we temp transform
_temp_tran_cache	determines if temp table is created with cache option
_test_ksusigskip	test the function ksusigskip
_test_param_1	test parmeter 1 – integer
_test_param_2	test parameter 2 – string
_test_param_3	test parameter 3 – string
_test_param_4	test parameter 4 – string list
_test_param_5	test parmeter 5 – deprecated integer
_test_param_6	test parmeter 6 – size (ub8)
_test_spacebg	test space management background task
_third_spare_parameter	_threshold_alerts_enable		_timemodel_collection	enable timemodel collection
_timeout_actions_enabled	enables or disables KSU timeout actions
_timer_precision	VKTM sleep time in milli-sec
_total_large_extent_memory	Total memory for allocating large extents
_tq_dump_period	time period for duping of TQ statistics (s)
_trace_buffer_wait_timeouts	trace buffer busy wait timeouts
_trace_buffers	ALL:256	trace buffer sizes per process
_trace_dump_all_procs	if TRUE on error buckets of all processes will be dumped to the current trace file
_trace_dump_client_buckets	if TRUE dump client (ie. non-kst) buckets
_trace_dump_cur_proc_only	if TRUE on error just dump our process bucket
_trace_dump_static_only	if TRUE filter trace dumps to always loaded dlls
_trace_events	trace events enabled at startup
_trace_files_public	Create publicly accessible trace files
_trace_kqlidp	trace kqlidp0 operation
_trace_navigation_scope	enabling trace navigation linking
_trace_pin_time	trace how long a current pin is held
_trace_pool_size	trace pool size in bytes
_trace_processes	enable KST tracing in process
_trace_virtual_columns	trace virtual columns exprs
_transaction_auditing	transaction auditing records generated in the redo log
_transaction_recovery_servers	max number of parallel recovery slaves that may be used
_truncate_optimization_enabled	do truncate optimization if set to TRUE
_tsenc_tracing	Enable TS encryption tracing
_tsm_connect_string	TSM test connect string
_tsm_disable_auto_cleanup	disable TSM auto cleanup actions
_tts_allow_charset_mismatch	allow plugging in a tablespace with an incompatible character set
_two_pass	enable two-pass thread recovery
_two_pass_reverse_polish_enabled	uses two-pass reverse polish alg. to generate canonical forms
_uga_cga_large_extent_size	UGA/CGA large extent size
_ultrafast_latch_statistics	maintain fast-path statistics for ultrafast latches
_undo_autotune	enable auto tuning of undo_retention
_undo_block_compression	enable undo block compression
_undo_debug_mode	debug flag for undo related operations
_undo_debug_usage	invoke undo usage functions for testing
_union_rewrite_for_gs	YES_GSET_MVS	expand queries with GSets into UNIONs for rewrite
_unnest_subquery	enables unnesting of correlated subqueries
_unused_block_compression	enable unused block compression
_update_datafile_headers_with_space_information	user requested update of datafile headers of locally managed datafiles with space information
_use_best_fit	use best fit to allocate space
_use_column_stats_for_function	enable the use of column statistics for DDP functions
_use_ism	Enable Shared Page Tables – ISM
_use_ism_for_pga	Use ISM for allocating large extents
_use_nosegment_indexes	use nosegment indexes in explain plan
_use_realfree_heap	use real-free based allocator for PGA memory
_use_seq_process_cache	whether to use process local seq cache
_use_vector_post	use vector post
_use_zero_copy_io	Should network vector IO interface be used for data transfer
_validate_flashback_database	Scan database to validate result of flashback database
_vendor_lib_loc	vendor library search root directory
_verify_flashback_redo	Verify that the redo logs needed for flashback are available
_verify_undo_quota	TRUE – verify consistency of undo quota statistics
_very_large_partitioned_table	very_large_partitioned_table
_virtual_column_overload_allowed	overload virtual columns expression
_wait_breakup_threshold_csecs	Wait breakup threshold (in centiseconds)
_wait_breakup_time_csecs	Wait breakup time (in centiseconds)
_wait_for_sync	wait for sync on commit MUST BE ALWAYS TRUE
_walk_insert_threshold	maximum number of unusable blocks to walk across freelist
_watchpoint_on	is the watchpointing feature turned on?
_wcr_control	Oracle internal test WCR parameter used ONLY for testing!
_windowfunc_optimization_settings	settings for window function optimizations
_with_subquery	OPTIMIZER	WITH subquery transformation
_write_clones	write clones flag
_xpl_peeked_binds_log_size	maximum bytes for logging peeked bind values for V$sql_PLAN (0 = OFF)
_xpl_trace	Explain Plan tracing parameter
_xsolapi_auto_materialization_bound	OLAP API lower bound for auto materialization.
_xsolapi_auto_materialization_type	PRED_AND_RC	OLAP API behavior for auto materialization
_xsolapi_build_trace	OLAP API output build info to trace file
_xsolapi_debug_output	SUPPRESS	OLAP API debug output disposition
_xsolapi_densify_cubes	TABULAR	OLAP API cube densification
_xsolapi_dimension_group_creation	OVERFETCH	OLAP API symmetric overfetch
_xsolapi_dml_trace	OLAP API output dml commands and expressions to trace file
_xsolapi_fetch_type	PARTIAL	OLAP API fetch type
_xsolapi_fix_vptrs	OLAP API Enable vptr fixing logic in shared server mode
_xsolapi_generate_with_clause	OLAP API generates WITH clause?
_xsolapi_hierarchy_value_type	unique	OLAP API hierarchy value type
_xsolapi_load_at_process_start	NEVER	When to load OLAP API library at server process start
_xsolapi_materialization_rowcache_min_rows_for_use	OLAP API min number of rows required to use rowcache in query materialization
_xsolapi_materialize_sources	OLAP API Enable source materialization
_xsolapi_Metadata_reader_mode	11_ONLY	OLAP API Metadata reader mode
_xsolapi_odbo_mode	OLAP API uses ODBO mode?
_xsolapi_opt_aw_position	OLAP API enables AW position and count optimization?
_xsolapi_optimize_suppression	OLAP API optimizes suppressions?
_xsolapi_precompute_subquery	OLAP API precomputes subqueries?
_xsolapi_remove_columns_for_materialization	OLAP API removes columns for materialization?
_xsolapi_set_nls	OLAP API sets NLS?
_xsolapi_share_executors	OLAP API share executors?
_xsolapi_source_trace	OLAP API output Source deFinitions to trace file
_xsolapi_sql_all_multi_join_non_base_hints	OLAP API multi-join non-base hints
_xsolapi_sql_all_non_base_hints	OLAP API non-base hints
_xsolapi_sql_auto_dimension_hints	OLAP API enable automatic dimension hints
_xsolapi_sql_auto_measure_hints	OLAP API enable automatic measure hints
_xsolapi_sql_dimension_hints	OLAP API dimension hints
_xsolapi_sql_enable_aw_join	OLAP API enables AW join?
_xsolapi_sql_enable_aw_qdr_merge	OLAP API enables AW QDR merge?
_xsolapi_sql_hints	OLAP API generic hints
_xsolapi_sql_measure_hints	OLAP API measure hints
_xsolapi_sql_minus_threshold	OLAP API sql MINUS threshold
_xsolapi_sql_optimize	OLAP API enable optimization
_xsolapi_sql_prepare_stmt_cache_size	OLAP API prepare statement cache size
_xsolapi_sql_remove_columns	OLAP API enable remove unused columns optimizations
_xsolapi_sql_result_set_cache_size	OLAP API result set cache size
_xsolapi_sql_symmetric_predicate	OLAP API enable symmetric predicate for dimension groups
_xsolapi_sql_top_dimension_hints	OLAP API top dimension hints
_xsolapi_sql_top_measure_hints	OLAP API top measure hints
_xsolapi_sql_use_bind_variables	OLAP API enable bind variables optimization
_xsolapi_stringify_order_levels	OLAP API stringifies order levels?
_xsolapi_support_mtm	OLAP API MTM mapping classes supported?
_xsolapi_suppression_aw_mask_threshold	OLAP API suppression AW mask threshold
_xsolapi_suppression_chunk_size	OLAP API suppression chunk size
_xsolapi_use_models	OLAP API uses models?
_xsolapi_use_olap_dml	OLAP API uses OLAP DML?
_xsolapi_use_olap_dml_for_rank	OLAP API uses OLAP DML for rank?
_xt_coverage	external tables code coverage parameter
_xt_trace	external tables trace parameter
_xtbuffer_size	buffer size in KB needed for populate/query operation
_xtts_allow_pre10	allow cross platform for pre10 compatible tablespace
_xtts_set_platform_info	set cross platform info during file header read
_yield_check_interval	interval to check whether actses should yield