From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCH V5 8/8] blk-mq: improve bio merge from blk-mq sw queue
Date: Tue, 3 Oct 2017 02:21:43 -0700
Message-ID: <20171003092143.GF2771@infradead.org>
References: <20170930112655.31451-1-ming.lei@redhat.com>
 <20170930112655.31451-9-ming.lei@redhat.com>
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This looks generally good to me, but I really worry about the impact
on very high iops devices.  Did you try this e.g. for random reads
from unallocated blocks on an enterprise NVMe SSD?