MemFree from /proc/meminfo

Shell Programming and Scripting
1

From the following /proc/meminfo output only ~2GB is free out of total 250GB, but Cached is 194630300 kB. My customer is concerned over the very little memory showing as free. Kindly shed some light if the free memory available in this situation is some thing we need to worry or can we take it as expected behavior of Linux kernel - as most of them are cached.
Linux 2.6.39-400.277.1.el6uek.x86_64

MemTotal:       264082720 kB
MemFree:         2114036 kB
Buffers:          417188 kB
Cached:         194630300 kB
SwapCached:          172 kB
Active:         12577096 kB
Inactive:       189334136 kB
Active(anon):    6788124 kB
Inactive(anon):   221452 kB
Active(file):    5788972 kB
Inactive(file): 189112684 kB
Unevictable:      494788 kB
Mlocked:          494836 kB
SwapTotal:      25165820 kB
SwapFree:       25160384 kB
Dirty:              2008 kB
Writeback:           108 kB
AnonPages:       7402208 kB
Mapped:           260780 kB
Shmem:              1012 kB
Slab:            1532520 kB
SReclaimable:    1201976 kB
SUnreclaim:       330544 kB
KernelStack:       19200 kB
PageTables:       385236 kB
NFS_Unstable:          0 kB
Bounce:                0 kB
WritebackTmp:          0 kB
CommitLimit:    130992780 kB
Committed_AS:   12763688 kB
VmallocTotal:   34359738367 kB
VmallocUsed:     1178180 kB
VmallocChunk:   34224213544 kB
HardwareCorrupted:     0 kB
HugePages_Total:   25600
HugePages_Free:    14820
HugePages_Rsvd:        0
HugePages_Surp:        0
Hugepagesize:       2048 kB
DirectMap4k:        8192 kB
DirectMap2M:     2023424 kB
DirectMap1G:    266338304 kB
2

Good news: This is entirely expected and there is no cause for worry at all.

The kernel will use any idle memory for disk cache but gives it up easily at need; you can consider it as "free" memory. It quickly tops the charts on any lightly-loaded Linux system. This just means the memory isn't being used for much else.

"Free" is a somewhat misleading title and just designates wasted memory which is being used for absolutely nothing whatsoever, not even disk cache.

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3

Thanks Corona688 for the information.

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