postgresql – 如何修复Postgres以便在突然关闭后启动它？

由于突然断电,在我的本地机器上运行的PostGres服务器突然关闭.重新启动后,我尝试重新启动postgres,我收到此错误：

$pg_ctl -D /usr/local / pgsql / data restart

pg_ctl: PID file "/usr/local/pgsql/data/postmaster.pid" does not exist
Is server running?
starting server anyway
server starting
$:/usr/local/pgsql/data$LOG:  database system shutdown was interrupted at 2009-02-28 21:06:16 
LOG:  checkpoint record is at 2/8FD6F8D0
LOG:  redo record is at 2/8FD6F8D0; undo record is at 0/0; shutdown FALSE
LOG:  next transaction ID: 0/1888104; next OID: 1711752
LOG:  next MultixactId: 2; next MultixactOffset: 3
LOG:  database system was not properly shut down; automatic recovery in progress
LOG:  redo starts at 2/8FD6F918
LOG:  record with zero length at 2/8FFD94A8
LOG:  redo done at 2/8FFD9480
LOG:  Could not fsync segment 0 of relation 1663/1707047/1707304: No such file or directory
FATAL:  storage sync Failed on magnetic disk: No such file or directory
LOG:  startup process (PID 5465) exited with exit code 1
LOG:  aborting startup due to startup process failure

数据目录中没有postmaster.pid文件.什么可能是这种行为的原因,当然还有出路？

您需要 pg_resetxlog.虽然此后您的数据库可能处于不一致状态,因此请使用pg_dumpall转储它,重新创建并导回.

原因可能是：

>您还没有关闭硬件
经常在磁盘上写缓存
防止操作系统在报告成功写入应用程序之前确保写入数据.检查

hdparm -I / dev / sda

如果它在“写入缓存”之前显示“*”,则可能是这种情况. Source of PostgreSQL有一个程序src / tools / fsync / test_fsync.c,它测试与磁盘同步数据的速度.运行它 – 如果它报告的所有时间都比磁盘所在的时间短3秒 – 在7500rpm的磁盘上,1000次写入相同位置的测试需要至少8秒才能完成(1000 /(7500rpm /) 60s))因为每条路线只能写一次.如果您的数据库位于/ var / tmp分区之外的另一个磁盘上,则需要编辑此test_fsync.c – 更改

#define FSYNC_FILENAME“/var/tmp/test_fsync.out”

至

#define FSYNC_FILENAME“/usr/local/pgsql/data/test_fsync.out”
>您的磁盘出现故障并且存在坏块,请查看badblocks.
>你的内存不好,请在memtest86+查询至少8小时.