From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: dm-crypt parallelization patches Date: Tue, 9 Apr 2013 12:52:59 -0700 Message-ID: <20130409195259.GL6186@mtj.dyndns.org> References: <20130328185327.GF14088@htj.dyndns.org> <20130328193343.GA15969@redhat.com> <20130328194443.GG14088@htj.dyndns.org> <20130328203808.GC15969@redhat.com> <20130328204522.GA25501@mtj.dyndns.org> <20130409175753.GA6186@mtj.dyndns.org> <20130409181031.GC6186@mtj.dyndns.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Mikulas Patocka Cc: Jens Axboe , Vivek Goyal , Mike Snitzer , Milan Broz , dm-devel@redhat.com, Andi Kleen , dm-crypt@saout.de, linux-kernel@vger.kernel.org, Christoph Hellwig , Christian Schmidt List-Id: dm-devel.ids On Tue, Apr 09, 2013 at 03:42:16PM -0400, Mikulas Patocka wrote: > If I drop ifdefs, it doesn't compile (because other cgroup stuff it > missing). > > So I enabled bio cgroups. > > bio_associate_current can't be used, because by the time we allocate the > outgoing write bio, we are no longer in the process that submitted the > original bio. Oh, I suppose it'd need some massaging to selectively turn off the cgroup part. > Anyway, I tried to reproduce in dm-crypt what bio_associate_current does - and we probably need to change that to bio_associate_task(). > in the submitting process I record "ioc" and "css" fields in "dm_crypt_io" > structure and set these fields on all outgoing bios. It has no effect on > performance, it is as bad as if I hadn't done it. A good way to verify that the tagging is correct would be configuring io limits in block cgroup and see whether the limits are correctly applied when going through dm-crypt (please test with direct-io or reads, writeback is horribly broken, sorry).working correctly, maybe plugging is the overriding factor? Thanks. -- tejun