Proc/Meminfo - Red Hat ENTERPRISE LINUX 5 - DEPLOYMENT Deployment Manual

The /proc/mdstat file below shows a system with its md0 configured as a RAID 1 device, while it is
currently re-syncing the disks:
Personalities : [linear] [raid1] read_ahead 1024 sectors
md0: active raid1 sda2[1] sdb2[0] 9940 blocks [2/2] [UU] resync=1% finish=12.3min algorithm 2
[3/3] [UUU]
unused devices: <none>

3.2.19. /proc/meminfo

This is one of the more commonly used files in the /proc/ directory, as it reports a large amount of
valuable information about the systems RAM usage.
The following sample /proc/meminfo virtual file is from a system with 256 MB of RAM and 512 MB
of swap space:
MemTotal: 255908 kB
MemFree: 69936 kB
Buffers: 15812 kB
Cached: 115124 kB
SwapCached:
Active: 92700 kB
Inactive: 63792 kB
HighTotal:
HighFree:
LowTotal: 255908 kB
LowFree: 69936 kB
SwapTotal: 524280 kB
SwapFree: 524280 kB
Dirty:
Writeback:
Mapped: 42236 kB
Slab: 25912 kB
Committed_AS: 118680 kB
PageTables: 1236 kB
VmallocTotal: 3874808 kB
VmallocUsed: 1416 kB
VmallocChunk: 3872908 kB
HugePages_Total:
HugePages_Free:
Hugepagesize: 4096 kB
Much of the information here is used by the free, top, and ps commands. In fact, the output of the
free command is similar in appearance to the contents and structure of /proc/meminfo. But by
looking directly at /proc/meminfo, more details are revealed:
• MemTotal — Total amount of physical RAM, in kilobytes.
• MemFree — The amount of physical RAM, in kilobytes, left unused by the system.
• Buffers — The amount of physical RAM, in kilobytes, used for file buffers.
• Cached — The amount of physical RAM, in kilobytes, used as cache memory.
• SwapCached — The amount of swap, in kilobytes, used as cache memory.
0 kB
0 kB
0 kB
4 kB
0 kB
0
0
/proc/meminfo
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