From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43245) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1anMru-0007V5-Fv for qemu-devel@nongnu.org; Tue, 05 Apr 2016 05:01:51 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1anMrs-0005lU-Lk for qemu-devel@nongnu.org; Tue, 05 Apr 2016 05:01:50 -0400 Received: from mail-lf0-x244.google.com ([2a00:1450:4010:c07::244]:36456) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1anMrs-0005lI-BP for qemu-devel@nongnu.org; Tue, 05 Apr 2016 05:01:48 -0400 Received: by mail-lf0-x244.google.com with SMTP id p81so633543lfb.3 for ; Tue, 05 Apr 2016 02:01:48 -0700 (PDT) Sender: Paolo Bonzini References: <1459834253-8291-1-git-send-email-cota@braap.org> From: Paolo Bonzini Message-ID: <57037EF7.8040604@redhat.com> Date: Tue, 5 Apr 2016 11:01:43 +0200 MIME-Version: 1.0 In-Reply-To: <1459834253-8291-1-git-send-email-cota@braap.org> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 00/10] tb hash improvements List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Emilio G. Cota" , QEMU Developers , MTTCG Devel Cc: Peter Maydell , Sergey Fedorov , Richard Henderson , =?UTF-8?Q?Alex_Benn=c3=a9e?= , Peter Crosthwaite On 05/04/2016 07:30, Emilio G. Cota wrote: > This patchset is derived from my ongoing work on MTTCG, but does > not depend on it and brings improvements that we can already > benefit from. It applies cleanly on the current master and > is checkpatch-clean. > > The key goal is to make the TB hash table faster, and while at it, > scalable. Tested on two different host machines, the execution time > improvement before and after this series, when booting a debian > jessie arm image[*] with arm-softmmu, is: > > - Intel Xeon E5-2690: 21.2% less time > - Intel i7-4790K: 23.5% less time > > This workload is particularly sensitive to TB hash performance. > Other workloads not as sensitive might see a slight performance > degradation with this patchset, since the hashing + lookup > functions take now more instructions. In any case, no significant > slowdowns should occur. > > The commit logs are sometimes long because I have lots of numbers > to share. > > The only bits I'm not too comfortable with in this series are patches > 2 and 5; I don't develop on Windows so I'm shooting in the dark there. > > Please take a look and if possible, test on workloads you care about! That's great stuff. It will have to wait for 2.7, but it's really good. Paolo