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From: Zhongkun He <hezhongkun.hzk@bytedance.com>
Date: Tue, 2 Jan 2024 22:09:41 +0800
Message-ID: <CACSyD1Oq_0+y=2LbbMEJPtnm4tQt61pbP=CnqtprKan5U3-cVQ@mail.gmail.com>
Subject: Re: [External] Re: [PATCH] mm: zswap: fix the lack of page lru flag
 in zswap_writeback_entry
To: Nhat Pham <nphamcs@gmail.com>
Cc: akpm@linux-foundation.org, hannes@cmpxchg.org, yosryahmed@google.com, 
	sjenning@redhat.com, ddstreet@ieee.org, vitaly.wool@konsulko.com, 
	linux-mm@kvack.org, linux-kernel@vger.kernel.org
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>
> Base:
>                      total        used        recalim        total        used
> Mem:           38Gi       2.5Gi       ---->             38Gi       1.5Gi
> Swap:         5.0Gi       1.0Gi       ---->              5Gi        1.5Gi
> used memory  -1G   swap +0.5g
> It means that  half of the pages are failed to move to the tail of lru list,
> So we need to release an additional 0.5Gi anon pages to swap space.

Based on the results of multiple tests, the following information is updated.

Base:
                      total        used        recalim        total        used
 Mem:           38Gi       2.6Gi       ---->             38Gi       1.6Gi
 Swap:         5.0Gi       1.0Gi       ---->              5Gi        1.9Gi
 used memory  -1G   swap +0.9g
It means that  most of the pages failed to move to the tail of the lru list,
So we need to release an additional 0.9Gi anon pages to swap space.

Thanks again.