On Mon, 12 Sep 2011 12:57:18 +0200 Johannes Weiner <jweiner@xxxxxxxxxx> wrote: > Memory control groups are currently bolted onto the side of > traditional memory management in places where better integration would > be preferrable. To reclaim memory, for example, memory control groups > maintain their own LRU list and reclaim strategy aside from the global > per-zone LRU list reclaim. But an extra list head for each existing > page frame is expensive and maintaining it requires additional code. > > This patchset disables the global per-zone LRU lists on memory cgroup > configurations and converts all its users to operate on the per-memory > cgroup lists instead. As LRU pages are then exclusively on one list, > this saves two list pointers for each page frame in the system: > > page_cgroup array size with 4G physical memory > > vanilla: [ 0.000000] allocated 31457280 bytes of page_cgroup > patched: [ 0.000000] allocated 15728640 bytes of page_cgroup > > At the same time, system performance for various workloads is > unaffected: > > 100G sparse file cat, 4G physical memory, 10 runs, to test for code > bloat in the traditional LRU handling and kswapd & direct reclaim > paths, without/with the memory controller configured in > > vanilla: 71.603(0.207) seconds > patched: 71.640(0.156) seconds > > vanilla: 79.558(0.288) seconds > patched: 77.233(0.147) seconds > > 100G sparse file cat in 1G memory cgroup, 10 runs, to test for code > bloat in the traditional memory cgroup LRU handling and reclaim path > > vanilla: 96.844(0.281) seconds > patched: 94.454(0.311) seconds > > 4 unlimited memcgs running kbuild -j32 each, 4G physical memory, 500M > swap on SSD, 10 runs, to test for regressions in kswapd & direct > reclaim using per-memcg LRU lists with multiple memcgs and multiple > allocators within each memcg > > vanilla: 717.722(1.440) seconds [ 69720.100(11600.835) majfaults ] > patched: 714.106(2.313) seconds [ 71109.300(14886.186) majfaults ] > > 16 unlimited memcgs running kbuild, 1900M hierarchical limit, 500M > swap on SSD, 10 runs, to test for regressions in hierarchical memcg > setups > > vanilla: 2742.058(1.992) seconds [ 26479.600(1736.737) majfaults ] > patched: 2743.267(1.214) seconds [ 27240.700(1076.063) majfaults ] > > This patch: > > There are currently two different implementations of iterating over a > memory cgroup hierarchy tree. > > Consolidate them into one worker function and base the convenience > looping-macros on top of it. > > Signed-off-by: Johannes Weiner <jweiner@xxxxxxxxxx> Seems nice. Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>