From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gleb Natapov Subject: Re: Seeking a KVM benchmark Date: Wed, 12 Nov 2014 17:32:30 +0200 Message-ID: <20141112153230.GD26187@minantech.com> References: <54608D77.2090907@redhat.com> <20141110104531.GB26187@minantech.com> <5460AC7C.8040409@redhat.com> <5460CA71.2050701@gmail.com> <5460F5B9.8030902@redhat.com> <20141110173835.GA26770@minantech.com> <5463458C.2070000@redhat.com> <20141112152204.GC26187@minantech.com> <54637C25.5000305@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Avi Kivity , Andy Lutomirski , kvm list To: Paolo Bonzini Return-path: Received: from mail-wi0-f171.google.com ([209.85.212.171]:53647 "EHLO mail-wi0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752885AbaKLPce (ORCPT ); Wed, 12 Nov 2014 10:32:34 -0500 Received: by mail-wi0-f171.google.com with SMTP id r20so5276660wiv.16 for ; Wed, 12 Nov 2014 07:32:33 -0800 (PST) Content-Disposition: inline In-Reply-To: <54637C25.5000305@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Wed, Nov 12, 2014 at 04:26:29PM +0100, Paolo Bonzini wrote: > > > On 12/11/2014 16:22, Gleb Natapov wrote: > >> > Nehalem results: > >> > > >> > userspace exit, urn 17560 17726 17628 17572 17417 > >> > lightweight exit, urn 3316 3342 3342 3319 3328 > >> > userspace exit, LOAD_EFER, guest!=host 12200 11772 12130 12164 12327 > >> > lightweight exit, LOAD_EFER, guest!=host 3214 3220 3238 3218 3337 > >> > userspace exit, LOAD_EFER, guest=host 11983 11780 11920 11919 12040 > >> > lightweight exit, LOAD_EFER, guest=host 3178 3193 3193 3187 3220 > >> > > > Is this with Andy's patch that skips LOAD_EFER when guest=host, or the one > > that always switch LOAD_EFER? > > Skip LOAD_EFER when guest=host. > So guest=host is a little bit better than guest!=host so looks like skipping LOAD_EFER helps, but why "lightweight exit, urn" worse than guest=host though, it should be exactly the same as long as NX bit is the same in urn test, no? -- Gleb.