From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753299Ab1LHKYX (ORCPT ); Thu, 8 Dec 2011 05:24:23 -0500 Received: from ozlabs.org ([203.10.76.45]:55822 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753231Ab1LHKYV (ORCPT ); Thu, 8 Dec 2011 05:24:21 -0500 From: Rusty Russell To: "Michael S. Tsirkin" , Sasha Levin Cc: Avi Kivity , linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, markmc@redhat.com Subject: Re: [PATCH] virtio-ring: Use threshold for switching to indirect descriptors In-Reply-To: <20111207154816.GA23845@redhat.com> References: <87zkfbre9x.fsf@rustcorp.com.au> <1322913028.3782.4.camel@lappy> <4EDB5EF0.2010909@redhat.com> <1323000831.4205.4.camel@lappy> <20111204162221.GB22501@redhat.com> <1323020088.3256.3.camel@lappy> <4EDBAFC5.2010405@redhat.com> <1323020374.3256.5.camel@lappy> <1323023039.3256.7.camel@lappy> <1323266565.4009.10.camel@lappy> <20111207154816.GA23845@redhat.com> User-Agent: Notmuch/0.6.1-1 (http://notmuchmail.org) Emacs/23.3.1 (i686-pc-linux-gnu) Date: Thu, 08 Dec 2011 20:14:20 +1030 Message-ID: <87r50fgzyj.fsf@rustcorp.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 7 Dec 2011 17:48:17 +0200, "Michael S. Tsirkin" wrote: > On Wed, Dec 07, 2011 at 04:02:45PM +0200, Sasha Levin wrote: > > On Sun, 2011-12-04 at 20:23 +0200, Sasha Levin wrote: > > > > [snip] > > > > Rusty, Michael, does the below looks a reasonable optimization for you? > > OK overall but a bit hard to say for sure as it looks pretty incomplete ... A static threshold is very hackish; we need to either initialize it to a proven-good value (since noone will ever change it) or be cleverer. Thanks, Rusty.