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Message-ID: <ed4926d1-aba5-0234-7345-cc3290e8cc54@kernel.org>
Date:   Wed, 17 May 2023 10:32:00 +0800
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Subject: Re: [f2fs-dev] Is compression available under direct-io mode?
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To:     Sijie Lan <sijielan@gmail.com>, linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net
References: <CAGAHmYC8AR_iw=nXQc6s29T3SkSoz9Ajd0N39Nv87orJJHMLGQ@mail.gmail.com>
From:   Chao Yu <chao@kernel.org>
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On 2023/5/12 9:10, Sijie Lan wrote:
> Hi, guys,
> 
> When I do some specific test scenarios, I want to do some direct write
> after data have been compressed in F2FS, but when I track the internal
> functions, it seems F2FS forces my direct-io request to buffer-io
> mode. Does it mean we can not do the write direct-io if we applied the

Yes, compression feature depends on page cache.

Thanks,

> compression feature? In other words, must f2fs use an inside buffer to
> provide compression functions?
> 
> 
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