From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:40760) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R0GiF-0000Da-QV for qemu-devel@nongnu.org; Sun, 04 Sep 2011 13:42:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1R0GiE-0007Kk-Bp for qemu-devel@nongnu.org; Sun, 04 Sep 2011 13:42:31 -0400 Received: from lo.gmane.org ([80.91.229.12]:59217) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R0GiE-0007Ka-6D for qemu-devel@nongnu.org; Sun, 04 Sep 2011 13:42:30 -0400 Received: from list by lo.gmane.org with local (Exim 4.69) (envelope-from ) id 1R0GiA-0003Uv-4j for qemu-devel@nongnu.org; Sun, 04 Sep 2011 19:42:26 +0200 Received: from brigitte.kvy.fi ([83.143.58.51]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Sun, 04 Sep 2011 19:42:26 +0200 Received: from ananaza by brigitte.kvy.fi with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Sun, 04 Sep 2011 19:42:26 +0200 From: Antti P Miettinen Date: Sun, 04 Sep 2011 20:42:10 +0300 Message-ID: <8762l8cih9.fsf@iki.fi> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Subject: Re: [Qemu-devel] emulated ARM performance vs real processor ? List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Julien Heyman writes: > Hi, > > I was wondering if anyone had some data regarding the relative performance of > any given ARM board emulated in QEMU versus the real thing. Yes, I do know > this depends a lot on the host PC running qemu, but some ballpark/example > figures would help. Say, I emulate a 400 Mhz ARM9 processor on a Core2Duo > laptop @ 2 Ghz, what kind of performance/timing ratio should I expect, one way > or the other ? For example, for boot time. > I have no idea whether the overhead of emulation is over-compensated by the > huge processing power of the host compared to the real HW target, and by which > factor. > > Regards, > Julien > Taking a look at: http://adt.cs.upb.de/quf/quf2011_proceedings.pdf page 20 (24th page in the PDF), figure 1b, the noprof bars, I'd expect 2GHz host to be on average faster than native target. The emulation speed depends on how core intensive vs memory intensive your workload is. Workloads that are memory bound in the target (e.g. gzip ASCII compression) can me emulated much faster (e.g. factor of two) than core bound workloads (e.g. mcrypt encryption). -- http://www.iki.fi/~ananaza/