From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1M8MPv-0007mP-JZ for qemu-devel@nongnu.org; Sun, 24 May 2009 18:43:43 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1M8MPr-0007hz-TE for qemu-devel@nongnu.org; Sun, 24 May 2009 18:43:43 -0400 Received: from [199.232.76.173] (port=55351 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1M8MPr-0007hw-Pe for qemu-devel@nongnu.org; Sun, 24 May 2009 18:43:39 -0400 Received: from bsdimp.com ([199.45.160.85]:52032 helo=harmony.bsdimp.com) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1M8MPr-0004Nh-7h for qemu-devel@nongnu.org; Sun, 24 May 2009 18:43:39 -0400 Date: Sun, 24 May 2009 16:40:41 -0600 (MDT) Message-Id: <20090524.164041.2077911892.imp@bsdimp.com> Subject: Re: [Qemu-devel] [PATCH 2/2] set migration max downtime From: "M. Warner Losh" In-Reply-To: <4A19A56D.2020303@redhat.com> References: <4A192A67.8050801@redhat.com> <4A19A46E.1070308@us.ibm.com> <4A19A56D.2020303@redhat.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: avi@redhat.com Cc: aliguori@us.ibm.com, glommer@redhat.com, qemu-devel@nongnu.org In message: <4A19A56D.2020303@redhat.com> Avi Kivity writes: : Anthony Liguori wrote: : >> I prefer seconds (and bytes). : > : > As a floating point value? : : Yes. More than enough spacecraft have been lost due to errors in unit : conversion. Floating point values don't have enough resolution to represent picosecond precision with a unix time-scale range. Had one bug where a system mysteriously stopped working after the unix epoch got big enough that it could no longer compute the differences between events with enough precision to have a stable PLL for the controlled signals... Warner