From mboxrd@z Thu Jan 1 00:00:00 1970 From: kuas Subject: Hyperthreading network benchmark Date: Sat, 30 Oct 2004 21:32:25 -0400 Message-ID: <418440A9.4030307@users.sourceforge.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Sender: xen-devel-admin@lists.sourceforge.net Errors-To: xen-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: xen-devel-ml List-Id: xen-devel@lists.xenproject.org Hi all, I found enabling hyperthreading for Xen (the hypervisor layer) would degrade network performance. I wonder if the synchronization cost of Xen (the hypervisor) running on multi cores/multiprocessors environment is high (around 30 %). The benchmark I did is against Intel Pentium 2.4 MHz Hyperthreaded CPU and Gigabit network (ethernet and switch). I was using WebStone 2.5 benchmark against Apache 2.0.50-1.0 (FC1 httpd package). I was also running 2.4.27 for the domains kernel. The result I have: 1. Native: a. Hyperthread enabled: 370 Mb/sec b. Hyperthread disabled: 270-290 Mb/sec 2. Domain 0 has the same performance around: 270 Mb/sec 3. Domain 1: a, Hyperthreaded enabled, domain1 run on different core: 175-185 Mb/sec b. Hyperthreaded disabled or even if enabled domain 1 is forced to be in the same Core with domain 0: 255-265 Mb/sec Please note, I was only sending request to one domain at a time. It seems when the two domain ran in the same core we had higher performance. I wonder if any other people has done almost similar test and have similiar/opposite behavior. Are these behaviors make sense? Thanks in advance for any comments. Kuas. ------------------------------------------------------- This SF.Net email is sponsored by: Sybase ASE Linux Express Edition - download now for FREE LinuxWorld Reader's Choice Award Winner for best database on Linux. http://ads.osdn.com/?ad_id=5588&alloc_id=12065&op=click