On Wed, Jul 28, 2010 at 12:21:28PM +0900, KAMEZAWA Hiroyuki wrote: > On Wed, 28 Jul 2010 12:18:20 +0900 > KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> wrote: > > > > > Hmm, but page-allocation-time doesn't sound very good for me. > > > > > > > > > > Why? > > > > > > > As you wrote, by attaching ID when a page cache is added, we'll have > > much chances of free-rider until it's paged out. So, adding some > > reseting-owner point may be good. > > > > But considering real world usage, I may be wrong. > > There will not be much free rider in real world, especially at write(). > > Then, page-allocation time may be good. > > > > (Because database doesn't use page-cache, there will be no big random write > > application.) > > > > Sorry, one more reason. memory cgroup has much complex code for supporting > move_account, re-attaching memory cgroup per pages. > So, if you take care of task-move-between-groups, blkio-ID may have > some problems if you only support allocation-time accounting. I think initially we can just keep it simple for blkio controller and not move page charges across blkio cgroup when process moves. Vivek -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>