From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=37791 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PLH4u-0005Jm-BF for qemu-devel@nongnu.org; Wed, 24 Nov 2010 10:16:13 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PLH4t-0002mk-6u for qemu-devel@nongnu.org; Wed, 24 Nov 2010 10:16:12 -0500 Received: from mail-qw0-f45.google.com ([209.85.216.45]:56006) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PLH4t-0002mD-3L for qemu-devel@nongnu.org; Wed, 24 Nov 2010 10:16:11 -0500 Received: by qwb8 with SMTP id 8so4364663qwb.4 for ; Wed, 24 Nov 2010 07:16:10 -0800 (PST) Sender: Paolo Bonzini Message-ID: <4CED2C34.4000503@redhat.com> Date: Wed, 24 Nov 2010 16:16:04 +0100 From: Paolo Bonzini MIME-Version: 1.0 References: <9b23b9b4cee242591bdb356c838a9cfb9af033c1.1290552026.git.quintela@redhat.com> <20101124104010.GA23493@redhat.com> <20101124111442.GF23493@redhat.com> In-Reply-To: <20101124111442.GF23493@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] Re: [PATCH 09/10] Exit loop if we have been there too long List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: qemu-devel@nongnu.org, Juan Quintela On 11/24/2010 12:14 PM, Michael S. Tsirkin wrote: >> > buffered_file timer runs each 100ms. And we "try" to measure channel >> > bandwidth from there. If we are not able to run the timer, all the >> > calculations are wrong, and then stalls happens. > > So the problem is the timer in the buffered file abstraction? > Why don't we just flush out data if the buffer is full? It takes a lot to fill the buffer if you have many zero pages, and if that happens the guest is starved by the main loop filling the buffer. Paolo