Re: [PATCH 1/4] memcg: simplify page cache charging.

KAMEZAWA Hiroyuki
2011-12-19T00:02:36Z

On Fri, 16 Dec 2011 14:28:14 -0800
Andrew Morton <akpm@linux-foundation.org> wrote:

> On Wed, 14 Dec 2011 16:49:22 +0900
> KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> wrote:
>
> > Because of commit ef6a3c6311, FUSE uses replace_page_cache() instead
> > of add_to_page_cache(). Then, mem_cgroup_cache_charge() is not
> > called against FUSE's pages from splice.
>
> Speaking of ef6a3c6311 ("mm: add replace_page_cache_page() function"),
> may I pathetically remind people that it's rather inefficient?
>
> http://lkml.indiana.edu/hypermail/linux/kernel/1109.1/00375.html
>

IIRC, people says inefficient because it uses memcg codes for page-migration
for fixing up accounting. Now, We added replace-page-cache for memcg in
memcg-add-mem_cgroup_replace_page_cache-to-fix-lru-issue.patch

So, I think the problem originally mentioned is fixed.

I'll reconsinder LRU handling optimization after things seems to be good.

Thanks,
-Kame