Linux total memory is full but not showing any usage by any process but getting OOM  ,how to troubleshoot this ?




free -m
             total       used       free     shared    buffers     cached
Mem:         26181      25991        189          0          0         19
-/+ buffers/cache:      25971        210
Swap:        20479         24      20455

--

MemTotal:       26809844 kB
MemFree:          194184 kB
Buffers:             852 kB
Cached:            13016 kB
SwapCached:         2764 kB
Active:             8684 kB
Inactive:          14024 kB
Active(anon):       8080 kB
Inactive(anon):      708 kB
Active(file):        604 kB
Inactive(file):    13316 kB
Unevictable:           0 kB
Mlocked:               0 kB
SwapTotal:      20971512 kB
SwapFree:       20946568 kB
Dirty:                 4 kB
Writeback:             0 kB
AnonPages:          8652 kB
Mapped:             2360 kB
Shmem:                 0 kB
Slab:              46412 kB
SReclaimable:       4504 kB
SUnreclaim:        41908 kB
KernelStack:        2376 kB
PageTables:         2492 kB
NFS_Unstable:          0 kB
Bounce:                0 kB
WritebackTmp:          0 kB
CommitLimit:    21252848 kB
Committed_AS:     170056 kB
VmallocTotal:   34359738367 kB
VmallocUsed:      205192 kB
VmallocChunk:   34359487900 kB
HardwareCorrupted:     0 kB
AnonHugePages:         0 kB
HugePages_Total:   12816
HugePages_Free:    12816
HugePages_Rsvd:        0
HugePages_Surp:        0
Hugepagesize:       2048 kB
DirectMap4k:       75776 kB
DirectMap2M:    27187200 kB

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