From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Martin K. Petersen" <martin.petersen@oracle.com>
Subject: Re: [LSF/MM ATTEND] discuss blk-mq related to
	DM-multipath and status of XCOPY
Date: Thu, 08 Jan 2015 09:39:10 -0500
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Cc: Christoph Hellwig <hch@infradead.org>, device-mapper development <dm-devel@redhat.com>, "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>, "Martin K. Petersen" <martin.petersen@oracle.com>
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>>>>> "Hannes" == Hannes Reinecke <hare@suse.de> writes:

Hannes> But the array might prioritize 'normal' I/O requests, and treat
Hannes> XCOPY with a lower priority. So given enough load XCOPY might
Hannes> actually be slower than a normal copy ...

Yes, but may have lower impact on concurrent I/O.

-- 
Martin K. Petersen	Oracle Linux Engineering