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Message-ID: <2b37ce73-83dd-e572-9578-7bb045f1040b@kernel.dk>
Date:   Tue, 29 Mar 2022 06:46:35 -0600
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Subject: Re: [PATCH -next RFC 2/6] block: refactor to split bio thoroughly
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To:     Yu Kuai <yukuai3@huawei.com>, andriy.shevchenko@linux.intel.com,
        john.garry@huawei.com, ming.lei@redhat.com
Cc:     linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        yi.zhang@huawei.com
References: <20220329094048.2107094-1-yukuai3@huawei.com>
 <20220329094048.2107094-3-yukuai3@huawei.com>
From:   Jens Axboe <axboe@kernel.dk>
In-Reply-To: <20220329094048.2107094-3-yukuai3@huawei.com>
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On 3/29/22 3:40 AM, Yu Kuai wrote:
> Currently, the splited bio is handled first, and then continue to split
> the original bio. This patch tries to split the original bio thoroughly,
> so that it can be known in advance how many tags will be needed.

This makes the bio almost 10% bigger in size, which is NOT something
that is just done casually and without strong reasoning.

So please provide that, your commit message is completely missing
justification for why this change is useful or necessary. A good
commit always explains WHY the change needs to be made, yours is
simply stating WHAT is being done. The latter can be gleaned from
the code change anyway.

-- 
Jens Axboe