KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> wrote: > On Fri, 24 Jul 2009 14:44:16 +0900 (JST) > Ryo Tsuruta <ryov@xxxxxxxxxxxxx> wrote: > good solution to resolve such problem. > > > > > My point is "don't allow anyone to use bandwidth of others." > > > Considering job isolation, a thread who requests swap-out should be charg= > > > ed > > > against bandwidth. > > > > From another perspective, the swap-out is caused since the buggy > > process uses a large amount of memory, so it can be considered as > > the bandwidth of logging process is used due to the buggy process. > > > > Please consider the following case. If a thread who requests swap-out > > is charged, the thread is charged other threads' I/O. > > > > (1) -------- (2) > > Process A | | Process B > > mmaps a large area in --> | memory | <-- tries to allocate a page. > > the memory and writes | | > > data to there. -------- (3) > > | To get a free page, > > | the data written by Proc.A > > | is written out to the disk. > > V The I/O is done by using > > --------- Proc.B's bandwidth. > > | disk | > > --------- > > > > Thus I think that page owners should be charged against bandwidth. > > > Ok, no good way. yours is wrong, mine is wrong, too. > plz find 3rd way, reasonable. > > Below is brief thinking. > > "Why process A should be charged to I/O when it just maps anon memory ?" > I can't answer this. > > Even in yorr case, Process B requests memory and get penalty. It's > very natural, I think. > > In usual case, > - if process A maps ANON, there will be no I/O. > - if process A maps FILE, it will be charged to process A. > ok ? > > Under memory pressure, > - if process A maps ANON, swap I/O should be charged to process B. > - if process A maps FILE, I/O should be charged to process A. > maybe. I think that even process A maps ANON, it should be charged to process A because the memory pressure is caused by process A. It seems natual for me that a process which consumes more resources is more likely to get penalty. > Anyway, there will be ineraction with dirty_ratio of memcg (not implemeted yet) > and _Owner should be charged_ issue will be handled in this dirty_ratio layer. > More consideration is necessary, I think. I'll keep thinking how it should be done. Thanks, Ryo Tsuruta -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
