From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: First performance numbers Date: Fri, 19 Sep 2008 23:48:24 +0200 Message-ID: <20080919214824.GA11410@amd.com> References: <1221658886-14109-1-git-send-email-agraf@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Cc: kvm@vger.kernel.org, joro@8bytes.org, anthony@codemonkey.ws, avi@qumranet.com To: Alexander Graf Return-path: Received: from outbound-dub.frontbridge.com ([213.199.154.16]:14278 "EHLO IE1EHSOBE005.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751694AbYISVsh (ORCPT ); Fri, 19 Sep 2008 17:48:37 -0400 Content-Disposition: inline In-Reply-To: <1221658886-14109-1-git-send-email-agraf@suse.de> Sender: kvm-owner@vger.kernel.org List-ID: Ok, here are some performance numbers for nested svm. I ran kernbench -M on a virtual machine with 4G RAM and 1 VCPU (since nesting SMP guests do currently not work). I measured simple virtualization with a shadow paging guest on bare metal and within a nested guest (same guest image) on a nested paging enabled first level guest. | Shadow Guest (100%) | Nested Guest (X) | X -----------------+---------------------+-------------------+-------- Elapsed Time | 553.244 (1.21208) | 1185.95 (20.0365) | 214.363% User Time | 407.728 (0.987279) | 520.434 (8.55643) | 127.642% System Time | 144.828 (0.480645) | 664.528 (11.6648) | 458.839% Percent CPU | 99 (0) | 99 (0) | 100.000% Context Switches | 98265.2 (183.001) | 220015 (3302.74) | 223.899% Sleeps | 49397.8 (31.0274) | 49460.2 (364.84) | 100.126% So we have an overall slowdown in the first nesting level of more than 50%. Mostly because we spend so much time in the system level. Seems there is some work to do for performance improvements :-) Joerg -- | AMD Saxony Limited Liability Company & Co. KG Operating | Wilschdorfer Landstr. 101, 01109 Dresden, Germany System | Register Court Dresden: HRA 4896 Research | General Partner authorized to represent: Center | AMD Saxony LLC (Wilmington, Delaware, US) | General Manager of AMD Saxony LLC: Dr. Hans-R. Deppe, Thomas McCoy