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Date:   Fri, 23 Sep 2022 08:16:24 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Jens Axboe <axboe@kernel.dk>
Cc:     linux-block@vger.kernel.org, linux-scsi@vger.kernel.org,
        linux-nvme@lists.infradead.org
Subject: Re: [PATCHSET 0/5] Enable alloc caching and batched freeing for
 passthrough
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On Thu, Sep 22, 2022 at 12:28:00PM -0600, Jens Axboe wrote:
> This is good for a 10% improvement for passthrough performance. For
> a non-drive limited test case, passthrough IO is now more efficient
> than the regular bdev O_DIRECT path.

How so?  If it ends up faster we are doing something wrong in the
normal path as there should be no fundamental difference in the work
that is being done.