From mboxrd@z Thu Jan 1 00:00:00 1970 From: Emmanuel Lacour Subject: Using tools such as ionice inside guests Date: Wed, 18 May 2016 17:49:03 +0200 Message-ID: <573C8EEF.9060000@easter-eggs.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit To: kvm@vger.kernel.org Return-path: Received: from smtp-out-2.easter-eggs.com ([37.9.136.156]:52899 "EHLO smtp-out-2.easter-eggs.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753276AbcERPzG (ORCPT ); Wed, 18 May 2016 11:55:06 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by volubilis.easter-eggs.com (Postfix) with ESMTP id 7D80F15E0F for ; Wed, 18 May 2016 17:49:03 +0200 (CEST) Received: from coquelicot-s.easter-eggs.com (coquelicot-s.easter-eggs.com [109.190.110.196]) by volubilis.easter-eggs.com (Postfix) with ESMTP id 637B815E3B for ; Wed, 18 May 2016 17:49:03 +0200 (CEST) Received: from [IPv6:2001:41d0:fc96:b200:290:f5ff:fef1:9723] (unknown [IPv6:2001:41d0:fc96:b200:290:f5ff:fef1:9723]) by rose.easter-eggs.fr (Postfix) with ESMTPSA id 5677513E1 for ; Wed, 18 May 2016 17:49:03 +0200 (CEST) Sender: kvm-owner@vger.kernel.org List-ID: Dear kvm developpers/users, I just saw that a change has been made in the kernel so the only one scheduler available in guests for virtio-blk is now "none". Seems introduced by [1]. I tried to used ionice on a 3.16 guest with virtio-blk and in fact it no longer works because cfq is no longer available. Is there a way to use, inside a guest, a tool like ionice to set different IO priority in guests processes? It's very useful for loering down the performance impact of backups jobs for example. [1] - http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=a98755c559e0e944a44174883b74a97019e3a367