From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bernhard Schmidt Subject: linux-aio usable? Date: Mon, 8 Mar 2010 01:46:27 +0000 (UTC) Message-ID: To: kvm@vger.kernel.org Return-path: Received: from lo.gmane.org ([80.91.229.12]:45173 "EHLO lo.gmane.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752505Ab0CHBqy (ORCPT ); Sun, 7 Mar 2010 20:46:54 -0500 Received: from list by lo.gmane.org with local (Exim 4.69) (envelope-from ) id 1NoS3S-0007du-Vr for kvm@vger.kernel.org; Mon, 08 Mar 2010 02:46:46 +0100 Received: from ppp-88-217-21-175.dynamic.mnet-online.de ([88.217.21.175]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Mon, 08 Mar 2010 02:46:46 +0100 Received: from berni by ppp-88-217-21-175.dynamic.mnet-online.de with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Mon, 08 Mar 2010 02:46:46 +0100 Sender: kvm-owner@vger.kernel.org List-ID: Hi, sorry for this pretty generic question, I did not find any real pros and cons on the net anywhere, but I might just have missed them. In a pure x86_64 environment (~2.6.32 vanilla kernel, 0.12.3 qemu-kvm), is enabling linux-aio in KVM a good idea? What are the advantages/disadvantages? Are there any potential pitfalls? The reason I'm asking is that there has been some traffic on the list about it, so it seems to be something people want to get working. qemu-kvm in Ubuntu Lucid is currently not compiled with that option. I've made a local version with aio and it seems to work fine (and performs a bit better at first glance). Is there any reason one should not compile that feature by default? Does it do anything if not explicitly run with aio=native? Best Regards, Bernhard