On Tue, 19 Oct 2010 21:33:21 -0700 Greg Thelen <[email protected]> wrote:
> KAMEZAWA Hiroyuki <[email protected]> writes: > > > On Tue, 19 Oct 2010 10:00:15 +0900 > > KAMEZAWA Hiroyuki <[email protected]> wrote: > > > >> On Mon, 18 Oct 2010 17:39:44 -0700 > >> Greg Thelen <[email protected]> wrote: > >> > >> > If the current process is in a non-root memcg, then > >> > global_dirty_limits() will consider the memcg dirty limit. > >> > This allows different cgroups to have distinct dirty limits > >> > which trigger direct and background writeback at different > >> > levels. > >> > > >> > Signed-off-by: Andrea Righi <[email protected]> > >> > Signed-off-by: Greg Thelen <[email protected]> > >> > >> Reviewed-by: KAMEZAWA Hiroyuki <[email protected]> > >> > > Why FREEPAGES in memcg is not counted as dirtyable ? > > > > Thanks, > > -Kame > > I think that FREEPAGES is considered dirtyable. Below I include the > latest version of the code, which includes an improved version of > memcg_hierarchical_free_pages(). > > Notice that mem_cgroup_page_stat(MEMCG_NR_DIRTYABLE_PAGES) returns the > sum of: > 1. compute free pages using memcg_hierarchical_free_pages() > 2. mem_cgroup_read_stat(mem, LRU_ACTIVE_FILE) + > mem_cgroup_read_stat(mem, LRU_INACTIVE_FILE) > 3. if (mem_cgroup_can_swap(mem)) > ret += mem_cgroup_read_stat(mem, LRU_ACTIVE_ANON) + > mem_cgroup_read_stat(mem, LRU_INACTIVE_ANON) > > This algorithm is similar to how global (non-memcg) limits are computed > in global_dirtyable_memory(). > seems very nice. Thank you. -Kame > /* > * Return the number of the number of pages that the @mem cgroup could > allocate. > * If use_hierarchy is set, then this involves parent mem cgroups to find the > * cgroup with the smallest free space. > */ > static unsigned long long > memcg_hierarchical_free_pages(struct mem_cgroup *mem) > { > unsigned long free, min_free; > > min_free = global_page_state(NR_FREE_PAGES) << PAGE_SHIFT; > > while (mem) { > free = res_counter_read_u64(&mem->res, RES_LIMIT) - > res_counter_read_u64(&mem->res, RES_USAGE); > min_free = min(min_free, free); > mem = parent_mem_cgroup(mem); > } > > /* Translate free memory in pages */ > return min_free >> PAGE_SHIFT; > } > > /* > * mem_cgroup_page_stat() - get memory cgroup file cache statistics > * @item: memory statistic item exported to the kernel > * > * Return the accounted statistic value. > */ > s64 mem_cgroup_page_stat(enum mem_cgroup_nr_pages_item item) > { > struct mem_cgroup *mem; > struct mem_cgroup *iter; > s64 value; > > get_online_cpus(); > rcu_read_lock(); > mem = mem_cgroup_from_task(current); > if (mem && !mem_cgroup_is_root(mem)) { > /* > * If we're looking for dirtyable pages we need to evaluate > * free pages depending on the limit and usage of the parents > * first of all. > */ > if (item == MEMCG_NR_DIRTYABLE_PAGES) > value = memcg_hierarchical_free_pages(mem); > else > value = 0; > /* > * Recursively evaluate page statistics against all cgroup > * under hierarchy tree > */ > for_each_mem_cgroup_tree(iter, mem) > value += mem_cgroup_local_page_stat(iter, item); > } else > value = -EINVAL; > rcu_read_unlock(); > put_online_cpus(); > > return value; > } > _______________________________________________ Containers mailing list [email protected] https://lists.linux-foundation.org/mailman/listinfo/containers _______________________________________________ Devel mailing list [email protected] https://openvz.org/mailman/listinfo/devel
