From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:60101) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QMliu-0007tq-SH for qemu-devel@nongnu.org; Wed, 18 May 2011 14:43:57 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QMlit-0005K1-NB for qemu-devel@nongnu.org; Wed, 18 May 2011 14:43:56 -0400 Received: from e9.ny.us.ibm.com ([32.97.182.139]:59854) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QMlit-0005Jx-Kt for qemu-devel@nongnu.org; Wed, 18 May 2011 14:43:55 -0400 Received: from d01relay06.pok.ibm.com (d01relay06.pok.ibm.com [9.56.227.116]) by e9.ny.us.ibm.com (8.14.4/8.13.1) with ESMTP id p4IIEQ9V008131 for ; Wed, 18 May 2011 14:14:26 -0400 Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by d01relay06.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p4IIhqZ51302630 for ; Wed, 18 May 2011 14:43:52 -0400 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p4IChLdZ009888 for ; Wed, 18 May 2011 06:43:21 -0600 Message-ID: <4DD41363.3080402@linux.vnet.ibm.com> Date: Wed, 18 May 2011 11:43:47 -0700 From: Venkateswararao Jujjuri MIME-Version: 1.0 References: <1305661431-21289-1-git-send-email-jvrao@linux.vnet.ibm.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [V2 0/25] Async threading for VirtFS using glib threads & coroutines. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi Cc: aliguori@us.ibm.com, qemu-devel@nongnu.org, stefanha@linux.vnet.ibm.com On 05/18/2011 03:39 AM, Stefan Hajnoczi wrote: > On Tue, May 17, 2011 at 8:43 PM, Venkateswararao Jujjuri (JV) > wrote: > > I sent comments on individual patches. This is turning out nice, many > of the PDU handlers are now straight-line code that can be followed > easily. > Thanks. Yeah it is coming out nice. :-) >> o Redesigned to use bh as per Stefan's suggestion. >> This made the code very simple but is little less performant compared to V1. >> Anthony suggested to go-in with cleaner code and design (This version) and >> deal with the performance later. >> Just to put in perspective: >> Sequential Writes of creating 1GB files using ffsb >> o Write size 8k >> With bh: 66.9MB/sec >> Without bh (marshalling routines): 74.9 MB/sec >> >> o Write size 128k >> With bh: 117MB/sec >> Without bh (marshalling routines): 122MB/sec > It would be interesting to hack in a post-yield callback which is > invoked after yield transfers control back to the calling coroutine. > This avoids setting up a BH and notifying the iothread to invoke it. > I'm just suggesting this as an experiment to see if the BH mechanism > causes the performance degradation, not as a real solution. > Correct, plan is to get the functionality in first and then handle this area. Thanks, JV > Stefan >