linux-kernel – 如何在/ proc / meminfo中计算MemTotal

当我cat / proc / meminfo时,报告如下：

MemTotal:        2034284 kB
MemFree:         1432728 kB
Buffers:           16568 kB
Cached:           324864 kB
SwapCached:            0 kB
Active:           307344 kB
Inactive:         256916 kB
Active(anon):     223020 kB
Inactive(anon):    74372 kB
Active(file):      84324 kB
Inactive(file):   182544 kB
Unevictable:           0 kB
Mlocked:               0 kB
HighTotal:       1152648 kB
HighFree:         600104 kB
LowTotal:         881636 kB
LowFree:          832624 kB
SwapTotal:       4200960 kB
SwapFree:        4200960 kB
Dirty:                60 kB
Writeback:             0 kB
AnonPages:        222868 kB
Mapped:            80596 kB
Shmem:             74564 kB
Slab:              24268 kB
SReclaimable:      14024 kB
SUnreclaim:        10244 kB
KernelStack:        1672 kB
PageTables:         2112 kB
NFS_Unstable:          0 kB
Bounce:                0 kB
WritebackTmp:          0 kB
CommitLimit:     5218100 kB
Committed_AS:     833352 kB
VmallocTotal:     122880 kB
VmallocUsed:       13916 kB
VmallocChunk:      50540 kB
HugePages_Total:       0
HugePages_Free:        0
HugePages_Rsvd:        0
HugePages_Surp:        0
Hugepagesize:       4096 kB
DirectMap4k:       20472 kB
DirectMap4M:      888832 kB

我有一个公式来计算Memtotal：

Memtotal = MemFree Cached Active Inactive Mapped Shmem Slab PageTables VmallocUsed

但我不知道公式是否正确,任何人都可以帮助澄清它？

解决方法

我认为很难达到meminfo的确切值(基于总内存验证的加法).
尽管如此,在我看来,接下来应该会让你接近TotalMemory数字.

TotalMemory = MemFree Buffers Cached Dirty AnonPages Slab VmAllocUsed

在您的示例中
1432728 16568 324864 60 222868 24268 13916 = 2035272
一些参考：
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/filesystems/proc.txt?id=HEAD#l451(来自上面建议的另一个stackoverflow文章)除此之外,我认为波动是因为VmAllocUsed.