From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=47423 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PNeYd-00041T-5y for qemu-devel@nongnu.org; Tue, 30 Nov 2010 23:45:05 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PNQwi-0006kx-SN for qemu-devel@nongnu.org; Tue, 30 Nov 2010 09:12:41 -0500 Received: from mx1.redhat.com ([209.132.183.28]:14588) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PNQwi-0006if-Jr for qemu-devel@nongnu.org; Tue, 30 Nov 2010 09:12:40 -0500 Date: Tue, 30 Nov 2010 16:11:50 +0200 From: "Michael S. Tsirkin" Message-ID: <20101130141150.GB20536@redhat.com> References: <20101124104035.GB23493@redhat.com> <4CF46012.2060804@codemonkey.ws> <4CF50410.3080305@codemonkey.ws> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4CF50410.3080305@codemonkey.ws> Subject: [Qemu-devel] Re: [PATCH 02/10] Add buffered_file_internal constant List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anthony Liguori Cc: qemu-devel@nongnu.org, Juan Quintela On Tue, Nov 30, 2010 at 08:02:56AM -0600, Anthony Liguori wrote: > If we're burning excess CPU walking a 100MB bitmap, then let's fix > that problem. Stopping every 1MB worth of the bitmap to do other > work just papers over the real problem (that we're walking 100MB > bitmap). Just using a bit per page will already make the problem 8x smaller, won't it? Is that enough to avoid the need for a new kernel interface? -- MST