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Date:   Mon, 21 Nov 2022 00:03:02 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Damien Le Moal <damien.lemoal@opensource.wdc.com>
Cc:     Ming Lei <ming.lei@redhat.com>,
        Andreas Hindborg <andreas.hindborg@wdc.com>,
        Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org
Subject: Re: Reordering of ublk IO requests
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I've been wading through this thread a bit, and while I can't follow
everything due some pretty bad reply trimming I'm really really
confused by this whole discussion.

Every single storage system, be that hard drives, SSDs, file systems
or what else much preferres sequential write.  Any code that turns
perfectly sequential writes into reverse sequential writes is a massive
performance bug, zoned or not.

So totally independent of zone device support in ublk this needs to be
fixed ASAP.