From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57711) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dECJQ-0000lO-Of for qemu-devel@nongnu.org; Fri, 26 May 2017 06:17:41 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dECJP-0006oX-Ur for qemu-devel@nongnu.org; Fri, 26 May 2017 06:17:40 -0400 Date: Fri, 26 May 2017 12:17:27 +0200 From: Kevin Wolf Message-ID: <20170526101727.GF7211@noname.str.redhat.com> References: <142326a3-eaa4-8333-9580-ae0063f8a876@redhat.com> <0e3fc298-d47b-4066-c8c8-02f620c50b89@virtuozzo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0e3fc298-d47b-4066-c8c8-02f620c50b89@virtuozzo.com> Subject: Re: [Qemu-devel] [PATCH 0/7] qcow2: Reduce the number of I/O ops when doing COW List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anton Nefedov Cc: Alberto Garcia , Eric Blake , qemu-devel@nongnu.org, qemu-block@nongnu.org, Max Reitz , Stefan Hajnoczi , "Denis V . Lunev" Am 24.05.2017 um 18:09 hat Anton Nefedov geschrieben: > I agree; as mentioned we have similar patches and they don't conflict much. > We noticed a performance regression on HDD though, for the > presumably optimized case (random 4k write over a large backed > image); so the patches were put on hold. You're talking about your own patches that should do the same thing, right? Can you re-do the same test with Berto's patches? Maybe there was just an implementation glitch in yours. This approach should very obviously result in a performance improvement, and the patches are relatively simple, so I'm very much inclined to merge this as soon as possible. Kevin