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Date:   Thu, 15 Jun 2023 16:20:49 +0200
From:   Michal Hocko <mhocko@suse.com>
To:     =?utf-8?B?6LS65Lit5Z2k?= <hezhongkun.hzk@bytedance.com>
Cc:     minchan@kernel.org, senozhatsky@chromium.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [External] Re: [RFC PATCH 1/3] zram: charge the compressed RAM
 to the page's memcgroup
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On Thu 15-06-23 22:13:09, 贺中坤 wrote:
> > This is not really answering my question though. memcg under hard limit
> > is not really my concern. This is a simpler case. I am not saying it
> > doesn't need to get addresses but it is the memcg hard limited case that
> > is much more interested. Because your charges are going to fail very
> > likely and that would mean that swapout would fail AFAIU. If my
> > understanding is wrong then it would really help to describe that case
> > much more in the changelog.
> >
> 
> OK, Got it. In many cases I have tested, it  will not fail because we did
> not charge the page directly，but the objects(like  slab,compressed page),
> for the zspage may be shared by any memcg.

That sounds like a broken design to me.
-- 
Michal Hocko
SUSE Labs