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Subject: Re: [f2fs-dev] [PATCH v2] f2fs: introduce blk_alloc_mode mount option
To:     Daeho Jeong <daeho43@gmail.com>
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        linux-f2fs-devel@lists.sourceforge.net, kernel-team@android.com,
        Daeho Jeong <daehojeong@google.com>
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From:   Chao Yu <chao@kernel.org>
Message-ID: <50bfbeee-e165-5bcf-1c47-a45ef8b36ebf@kernel.org>
Date:   Mon, 16 Aug 2021 15:43:36 +0800
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On 2021/8/16 15:11, Daeho Jeong wrote:
> I agree with you. But still I think "fragment" mode should work even
> in low free space conditions.
> Otherwise, it will be seeking the free blocks again and again like a busy loop.
> Or we can change the block allocation way into adaptive mode under low
> free space even staying in "fragment" mode.

I think fallbacking to adaptive mode sounds good to me, so the condition
of fallback may be there is no more free segments?

Thanks,

> 
> If we can handle this, we might use "fragment" mode for both
> simulating after fragmentation and making the filesystem fragmented.
>