Messages in this thread | | | Date | Fri, 28 Aug 2009 20:40:11 +0530 | From | Balbir Singh <> | Subject | Re: [RFC][PATCH 2/5] memcg: uncharge in batched manner |
| |
* KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> [2009-08-28 13:24:38]:
> > In massive parallel enviroment, res_counter can be a performance bottleneck. > This patch is a trial for reducing lock contention. > One strong techinque to reduce lock contention is reducing calls by > batching some amount of calls int one. > > Considering charge/uncharge chatacteristic, > - charge is done one by one via demand-paging. > - uncharge is done by > - in chunk at munmap, truncate, exit, execve... > - one by one via vmscan/paging. > > It seems we hace a chance to batched-uncharge. > This patch is a base patch for batched uncharge. For avoiding > scattering memcg's structure, this patch adds memcg batch uncharge > information to the task. please see start/end usage in next patch. >
Overall it is a very good idea, can't we do the uncharge at the poin tof unmap_vmas, exit_mmap, etc so that we don't have to keep additional data structures around.
-- Balbir
| |