KAMEZAWA Hiroyuki wrote: > On Fri, 19 Sep 2008 12:34:05 +0900 (JST) > Hirokazu Takahashi <taka@xxxxxxxxxxxxx> wrote: > >> I've decided to get Ryo to post the accurate dirty-page tracking patch >> for bio-cgroup, which isn't perfect yet though. The memory controller >> never wants to support this tracking because migrating a page between >> memory cgroups is really heavy. >> >> I also thought enhancing the memory controller would be good enough, >> but a lot of people said they wanted to control memory resource and >> block I/O resource separately. >> So you can create several bio-cgroup in one memory-cgroup, >> or you can use bio-cgroup without memory-cgroup. >> >> I also have a plan to implement more acurate tracking mechanism >> on bio-cgroup after the memory cgroup team re-implement the infrastructure, >> which won't be supported by memory-cgroup. >> When a process are moved into another memory cgroup, >> the pages belonging to the process don't move to the new cgroup >> because migrating pages is so heavy. It's hard to find the pages >> from the process and migrating pages may cause some memory pressure. >> I'll implement this feature only on bio-cgroup with minimum overhead >> > I really would like to move page_cgroup to new cgroup when the process moves... > But it's just in my plan and I'm not sure I can do it or not. > Kamezawa-San, I am not dead against it, but I would provide a knob/control point for system administrator to decide if movement is important for applications, then let them do so (like force_empty). > Anyway what's next for me is > 1. fix current discussion to remove page->page_cgroup pointer. > 2. reduce locks. Are you planning on reposting these. I've been trying other approaches at my end 1. Use radix tree per-node per-zone 2. Use radix trees only for 32 bit systems 3. Depend on CONFIG_HAVE_MEMORY_PRESENT and build a sparse data structure and use pre-allocation I've posted (1) and I'll take a look at your patches as well > 3. support swap and swap-cache. > > I think algorithm for (1), (2) is now getting smart. > Yes, it is getting better > Thanks, > -Kame > -- Balbir -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
