From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NpHMx-000400-0m for qemu-devel@nongnu.org; Wed, 10 Mar 2010 03:34:19 -0500 Received: from [199.232.76.173] (port=50839 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NpHMw-0003zd-HA for qemu-devel@nongnu.org; Wed, 10 Mar 2010 03:34:18 -0500 Received: from Debian-exim by monty-python.gnu.org with spam-scanned (Exim 4.60) (envelope-from ) id 1NpHMv-00031X-PN for qemu-devel@nongnu.org; Wed, 10 Mar 2010 03:34:18 -0500 Received: from mx1.redhat.com ([209.132.183.28]:20028) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1NpHMv-00031N-C2 for qemu-devel@nongnu.org; Wed, 10 Mar 2010 03:34:17 -0500 Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o2A8YDhA021634 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Wed, 10 Mar 2010 03:34:14 -0500 Message-ID: <4B97595B.9050005@redhat.com> Date: Wed, 10 Mar 2010 09:33:31 +0100 From: Kevin Wolf MIME-Version: 1.0 References: <1268175216-3600-1-git-send-email-lcapitulino@redhat.com> In-Reply-To: <1268175216-3600-1-git-send-email-lcapitulino@redhat.com> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] Re: [PATCH 0/3]: BLOCK_WATERMARK QMP event List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Luiz Capitulino Cc: uril@redhat.com, qemu-devel@nongnu.org Am 09.03.2010 23:53, schrieb Luiz Capitulino: > Hi, > > This series is based on a previous series submitted by Uri Lublin: > > http://lists.gnu.org/archive/html/qemu-devel/2009-03/msg00864.html > > Details on the patches, except for this question: does it make sense to have > a 'low' watermark for block devices? > > I think it doesn't, then the event (and the monitor accompanying command) > should be called BLOCK_HIGH_WATERMARK. But this makes the event very > unflexible, so I have called it BLOCK_WATERMARK and added parameters for the > high/low watermark type. When should a low watermark trigger? Images only ever grow, so testing if the highest allocated block goes below some watermark would never work (except for some unlikely special cases like deleting a snapshot after which no new clusters have been allocated). > It's a machine protocol, so I don't think the additional parameter > matters much. I don't think anyone is ever going to use it, but it probably wouldn't hurt either. Kevin