On Tue, 10 Jun 2008 14:50:32 +0900 (JST) yamamoto@xxxxxxxxxxxxx (YAMAMOTO Takashi) wrote: > > 3. Use Lazy Manner > > When the task moves, we can mark the pages used by it as > > "Wrong Charge, Should be dropped", and add them some penalty in the LRU. > > Pros. > > - no complicated ones. > > - the pages will be gradually moved at memory pressure. > > Cons. > > - A task's usage can exceed the limit for a while. > > - can't handle mlocked() memory in proper way. > > > > 4. Allow Half-moved state and abandon rollback. > > Pros. > > - no complicated ones in the code. > > Cons. > > - the users will be in chaos. > > how about: > > 5. try to move charges as your patch does. > if the target cgroup's usage is going to exceed the limit, > try to shrink it. if it failed, just leave it exceeded. > (ie. no rollback) > for the memory subsystem, which can use its OOM killer, > the failure should be rare. > Hmm, allowing exceed and cause OOM kill ? One difficult point is that the users cannot know they can move task without any risk. How to handle the risk can be a point. I don't like that approarch in general because I don't like "exceed" status. But implementation will be easy. > > After writing this patch, for me, "3" is attractive. now. > > (or using Lazy manner and allow moving of usage instead of freeing it.) > > > > One reasone is that I think a typical usage of memory controller is > > fork()->move->exec(). (by libcg ?) and exec() will flush the all usage. > > i guess that moving long-running applications can be desirable > esp. for not so well-designed systems. > hmm, for not so well-designed systems....true. But "5" has the same kind of risks for not so well-desgined systems ;) Thanks, -Kame _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers
