From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52024) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V7SLX-0002TX-59 for qemu-devel@nongnu.org; Thu, 08 Aug 2013 11:41:58 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1V7SLR-0003Gu-76 for qemu-devel@nongnu.org; Thu, 08 Aug 2013 11:41:51 -0400 Received: from nodalink.pck.nerim.net ([62.212.105.220]:54928 helo=paradis.irqsave.net) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V7SLQ-0003Gk-UF for qemu-devel@nongnu.org; Thu, 08 Aug 2013 11:41:45 -0400 Date: Thu, 8 Aug 2013 17:43:34 +0200 From: =?iso-8859-1?Q?Beno=EEt?= Canet Message-ID: <20130808154334.GA23734@irqsave.net> References: <1375972194-3090-1-git-send-email-benoit@irqsave.net> <1375972194-3090-4-git-send-email-benoit@irqsave.net> <5203B991.90405@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5203B991.90405@redhat.com> Subject: Re: [Qemu-devel] [PATCH V4 3/5] block: Enable the new throttling code in the block layer.o List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: kwolf@redhat.com, qemu-devel@nongnu.org, stefanha@redhat.com > This is not really accurate; the cfq scheduler reorders reads and writes > to have longer bursts, and these sometimes exceed the rate you set. I > understood this is mostly for separate rd/wr settings, or did you > reproduce it with "total" rates too? I'll drop the comment. It's only with read/write settings and not with total. > > Also, it would be better to have a workaround for this. Perhaps we > could simply make the default value of max nonzero? In the old > throttling code the slice time is 0.1s, so perhaps we could see what > happens with max=0.1*avg. I already set max to 0.1*avg if needed in the code.