This patchset implements targeted shrinking for memcg when kmem limits are present. So far, we've been accounting kernel objects but failing allocations when short of memory. This is because our only option would be to call the global shrinker, depleting objects from all caches and breaking isolation. The main idea is to associate per-memcg lists with each of the LRUs. The main LRU still provides a single entry point and when adding or removing an element from the LRU, we use the page information to figure out which memcg it belongs to and relay it to the right list. The bulk of the code is written by Glauber Costa. The only change I introduced myself in this iteration is reworking per-memcg LRU lists. Instead of extending the existing list_lru structure, which seems to be neat as is, I introduced a new one, memcg_list_lru, which aggregates list_lru objects for each kmem-active memcg and keeps them uptodate as memcgs are created/destroyed. I hope this simplified call paths and made the code easier to read. The patchset is based on top of Linux 3.12-rc6. Any comments and proposals are appreciated. == Known issues == * In case kmem limit is less than sum mem limit, reaching memcg kmem limit will result in an attempt to shrink all memcg slabs (see try_to_free_mem_cgroup_kmem()). Although this is better than simply failing allocation as it works now, it is still to be improved. * Since FS shrinkers can't be executed on __GFP_FS allocations, such allocations will fail if memcg kmem limit is less than sum mem limit and the memcg kmem usage is close to its limit. Glauber proposed to schedule a worker which would shrink kmem in the background on such allocations. However, this approach does not eliminate failures completely, it just makes them rarer. I'm thinking on implementing soft limits for memcg kmem so that striking the soft limit will trigger the reclaimer, but won't fail the allocation. I would appreciate any other proposals on how this can be fixed. * Only dcache and icache are reclaimed on memcg pressure. Other FS objects are left for global pressure only. However, it should not be a serious problem to make them reclaimable too by passing on memcg to the FS-layer and letting each FS decide if its internal objects are shrinkable on memcg pressure. == Changes from v10 == * Rework per-memcg list_lru infrastructure. Previous iteration (with full changelog) can be found here: http://www.spinics.net/lists/linux-fsdevel/msg66632.html Glauber Costa (12): memcg: make cache index determination more robust memcg: consolidate callers of memcg_cache_id vmscan: also shrink slab in memcg pressure memcg: move initialization to memcg creation memcg: move stop and resume accounting functions memcg: per-memcg kmem shrinking memcg: scan cache objects hierarchically vmscan: take at least one pass with shrinkers memcg: allow kmem limit to be resized down vmpressure: in-kernel notifications memcg: reap dead memcgs upon global memory pressure memcg: flush memcg items upon memcg destruction Vladimir Davydov (3): memcg,list_lru: add per-memcg LRU list infrastructure memcg,list_lru: add function walking over all lists of a per-memcg LRU super: make icache, dcache shrinkers memcg-aware fs/dcache.c | 25 +- fs/inode.c | 16 +- fs/internal.h | 9 +- fs/super.c | 47 +-- include/linux/fs.h | 4 +- include/linux/list_lru.h | 77 +++++ include/linux/memcontrol.h | 23 ++ include/linux/shrinker.h | 6 +- include/linux/swap.h | 2 + include/linux/vmpressure.h | 5 + mm/memcontrol.c | 704 +++++++++++++++++++++++++++++++++++++++----- mm/vmpressure.c | 53 +++- mm/vmscan.c | 178 +++++++++-- 13 files changed, 1014 insertions(+), 135 deletions(-) -- 1.7.10.4 -- 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>