free -hm outputs:
total used free shared buffers cached Mem: 15G 15G 389M 321M 169M 11G -/+ buffers/cache: 3.9G 11G Swap: 7.9G 80K 7.9G
The 'shared' column is the same as /proc/meminfo Shmem (332072 kb), but when I try to track down the processes that are using the shared memory with
ipcs -m, it only shows ~24MB usage:
------ Shared Memory Segments -------- key shmid owner perms bytes nattch status 0x00000000 851968 dangets 700 7978224 2 dest 0x00000000 458753 dangets 700 7978224 2 dest 0x00000000 589827 dangets 700 7978224 2 dest 0x0052e2c1 327684 postgres 600 48 5
Here's where I get fuzzier, so please correct me if I'm wrong.
I also looked for any
tmpfs mounts, and it is only the
/run mount, which
du -chs /run says that it only is 123MB.
Can someone please explain or point me to documentation on what actually contributes to the
/proc/meminfo Shmem field? Thanks!