From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:45776) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SWQL4-00045T-AB for qemu-devel@nongnu.org; Mon, 21 May 2012 06:59:47 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SWQL2-0001TC-LL for qemu-devel@nongnu.org; Mon, 21 May 2012 06:59:45 -0400 Received: from mx1.redhat.com ([209.132.183.28]:21052) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SWQL2-0001T2-DG for qemu-devel@nongnu.org; Mon, 21 May 2012 06:59:44 -0400 Message-ID: <4FBA201A.5040505@redhat.com> Date: Mon, 21 May 2012 12:59:38 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <4FBA1CC4.7020009@redhat.com> In-Reply-To: <4FBA1CC4.7020009@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] Weird iscsi/fd-event issue since recent merge of event system changes List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Kevin Wolf Cc: qemu-devel , ronnie sahlberg , Stefan Hajnoczi Il 21/05/2012 12:45, Kevin Wolf ha scritto: >> I have not yet found the exact part of this big patch that cause this >> slowdown, but will continue investigating. >> >> I am posting this here in case someone has any idea or if 55ms rings any bells. 55ms is the frequency of the PIT while the BIOS is running. I'd guess something is not waking up the iothread properly. > The only thing in this merge that looks as if it could be related is > Paolo's AIO changes between commit adfe92f6 and 9eb0bfca. > > Or if you use IDE, Stefan's patches to make PIO operations asynchronous > could be related. Yeah, both seem just as likely to be the culprit. Please bisect. Paolo