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Sender: Tejun Heo <htejun@gmail.com>
Date:   Tue, 7 Sep 2021 07:14:45 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Roman Gushchin <guro@fb.com>
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        Linus Torvalds <torvalds@linux-foundation.org>,
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        Zhengjun Xing <zhengjun.xing@linux.intel.com>
Subject: Re: [memcg] 0f12156dff: will-it-scale.per_process_ops -33.6%
 regression
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Hello,

On Tue, Sep 07, 2021 at 10:11:21AM -0700, Roman Gushchin wrote:
> There are two polar cases:
> 1) a big number of relatively short-living allocations, which lifetime is well
>    bounded (e.g. by a lifetime of a task),
> 2) a relatively small number of long-living allocations, which lifetime
>    is potentially indefinite (e.g. struct mount).
> 
> We can't use the same approach for both cases, otherwise we'll run into either
> performance or garbage collection problems (which also lead to performance
> problems, but delayed).

Wouldn't a front cache which expires after some seconds catch both cases?

Thanks.

-- 
tejun