From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1FTk2t-0002qf-Nn for qemu-devel@nongnu.org; Wed, 12 Apr 2006 14:26:27 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1FTk2t-0002pE-0W for qemu-devel@nongnu.org; Wed, 12 Apr 2006 14:26:27 -0400 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1FTk2s-0002ov-Fc for qemu-devel@nongnu.org; Wed, 12 Apr 2006 14:26:26 -0400 Received: from [204.127.200.84] (helo=sccrmhc14.comcast.net) by monty-python.gnu.org with esmtp (Exim 4.52) id 1FTk81-00048y-9x for qemu-devel@nongnu.org; Wed, 12 Apr 2006 14:31:45 -0400 Message-ID: <443D464F.7000304@win4lin.com> Date: Wed, 12 Apr 2006 14:26:23 -0400 From: "Leonardo E. Reiter" MIME-Version: 1.0 Subject: Re: [Qemu-devel] Re: Network Performance between Win Host and Linux References: <6fe044190604111020h47108190x23983325567fb51c@mail.gmail.com> <6fe044190604111536k944383o99ab27411d3864db@mail.gmail.com> <443D0909.3090806@win4lin.com> <6fe044190604121119r5a161123s77c0d7d13beaa637@mail.gmail.com> In-Reply-To: <6fe044190604121119r5a161123s77c0d7d13beaa637@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Ken, I'll check that on Linux-on-Linux... it's likely just some Windows overhead. Windows is my guest OS priority, which is why I tested on Windows. As for getting patches into the mainline, this is a job for the maintainers. Fabrice is the main person, but Paul Brook also merges a lot of patches in. I'm not sure what their process is, or to what extent they communicate with each other. I'm sure Paul and/or Fabrice would be kind enough to explain. I agree that there are lots of pending patches... in the case of yours specifically though, since it's so sweeping, I would guess that it probably needs more field testing before it becomes mainline. Regards, Leo Reiter Kenneth Duda wrote: > Leo, thank you for exercising this stuff. > > >>1. before your patches, the upstream transfers (guest->host) consumed >>almost no CPU at all, but of course were much slower. Now, about half >>the CPU gets used under heavy upstream load. > > > I am surprised that only half the CPU gets consumed --- that suggests > there's another factor of two improvement waiting to be made. If you > see anything like this with Linux-on-Linux, please let me know and > I'll try to track it down. > > Separately, I'm curious about the path for getting these changes into > the qemu mainline. If that's something you're in tune with and are in > the mood to summarize for me, I'd appreciate that. We love qemu but > there are some rough edges and I think we have something like 16 > patches we're maintaining internally, many of which might be helpful > for others. > > -Ken > > On 4/12/06, Leonardo E. Reiter wrote: > >>Hi Ken, >> >>(all) the patches seem to work very well and be very stable with Windows >>2000 guests here. I measured some SMB over TCP/IP transfers, and got >>about a 1.5x downstream improvement and a 2x upstream improvement. You >>will likely get more boost from less convoluted protocols like FTP or >>something, but I didn't get around to testing that. Plus it's not clear >>how much Windows itself is impeding the bandwidth. I am using >>-kernel-kqemu. >> >>2 additional things I noticed: >> >>1. before your patches, the upstream transfers (guest->host) consumed >>almost no CPU at all, but of course were much slower. Now, about half >>the CPU gets used under heavy upstream load. The downstream, with >>Windows guests at least, consumes 100% CPU the same as before. I >>suspect you addressed this specifically with your select hack to avoid >>the delay if there is pending slirp activity >> >>2. overall latency "feels" improved as well, at least for basic stuff >>like web browsing, etc. This is purely subjective. >> >>Nice work! I'll be testing with a Linux VM soon and try to pin down >>some better benchmarks, free of Windows clutter. >> >>- Leo Reiter > > > > _______________________________________________ > Qemu-devel mailing list > Qemu-devel@nongnu.org > http://lists.nongnu.org/mailman/listinfo/qemu-devel -- Leonardo E. Reiter Vice President of Product Development, CTO Win4Lin, Inc. Virtual Computing from Desktop to Data Center Main: +1 512 339 7979 Fax: +1 512 532 6501 http://www.win4lin.com