From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Gardner Subject: Re: trace default? Date: Wed, 07 Sep 2005 09:45:08 -0600 Message-ID: <431F0B04.6010801@hp.com> References: <431E1D6C.2070308@hp.com> <06f142c84884b47a710a8202eff3525f@cl.cam.ac.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <06f142c84884b47a710a8202eff3525f@cl.cam.ac.uk> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org Keir Fraser wrote: > > On 6 Sep 2005, at 23:51, Rob Gardner wrote: > >> The xen trace facility is not enabled by default. I'm working on some >> tools that use it, and I'm concerned that the tool will not work for >> customers who buy packaged distro's. What are the arguments for >> keeping trace disabled? Is it just the memory consumed by the trace >> buffers? It doesn't appear to me that there would be any impact >> beyond that. What is the possibility of making tracing enabled by >> default? > > > It's up to the distros to decide what options they anable in their > default Xen package imo. Yes, but they are likely to stick with the xen defaults unless they have a reason for changing them. In the case of tracing, their reaction is likely to be that "tracing" sounds like some debugging feature, will probably be bad for performance, so let's leave it turned off. So could you state what performance impact you think tracing will actually have on the system? Thanks, Rob