From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: dm: submit stacked requests in irq enabled context
Date: Wed, 10 May 2017 00:17:33 -0700
Message-ID: <20170510071733.GA24980@infradead.org>
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To: Keith Busch <keith.busch@intel.com>
Cc: Neeraj Soni <neersoni@codeaurora.org>, dm-devel@redhat.com, snitzer@redhat.com, Alasdair Kergon <agk@redhat.com>
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On Tue, May 09, 2017 at 11:55:55AM -0400, Keith Busch wrote:
> >      I have recently started using kernel 4.4 on a Android device and ran
> >      Androbench to check storage read/write performance. I found that the
> >      Random Read (RR) and Random write(RW) performance with Full Disk
> >      Encryption is degraded compared to no Disk Encryption. Initially i

dm-crypt doesn't even use request based device mapper.  Something odd
must be going on with your benchmarks.