On Thursday, February 12, 2015 11:34 PM, Konstantin Khlebnikov <koct9i@xxxxxxxxx> wrote: >> >> -bash-4.2$ sudo losetup -a >> /dev/loop0: [0005]:16512 (/dev/dm-2) >> -bash-4.2$ free -m >> total used free shared buffers cached >> Mem: 48094 46081 2012 40 40324 2085 >> -/+ buffers/cache: 3671 44422 >> Swap: 8191 5 8186 >> >> >> I've tried sysctl mm.vfs_cache_pressure=10000 but that seems working to Cached >> memory, I wonder is there another sysctl for reclaming Buffers? > AFAIK "Buffers" is just a page-cache of block devices. > From reclaimer's point of view they have no difference from file page-cache. > Could you post oom-killer log, there should be a lot of numbers > describing memory state. in this case, 40GB memory got stuck in Buffers, and 90+% of them are reclaimable (can be verified by vm.drop_caches manual reclaim) if Buffers are treated same as Cached, why mm.vfs_cache_pressure=10000 (or even I tried up to 1,000,000) can't get Buffers reclaimed early? I have some oom-killer msgs but were with older kernels, after set vm.overcommit_memory=2, it simply returns -ENOMEM, unable to spawn any new container, why doesn't it even try to reclaim some memory from those 40GB Buffers, Thanks, -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>