From mboxrd@z Thu Jan 1 00:00:00 1970 From: George Dunlap Subject: Re: [PATCH] xen: Implement domain runstates Date: Tue, 23 Nov 2010 15:48:33 +0000 Message-ID: <4CEBE251.6060009@eu.citrix.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: 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 On 23/11/10 15:00, Keir Fraser wrote: > Well, actually what we care about is #users-who-care. Plumbing into xentop > to satisfy an acceptance criteria is probably misguided. Reducing > patch-queue length just to make a patch-queue short is also probably > misguided. I wouldn't offer to put it in xentop just because I wanted to get the patch out of the patchqueue. I think it's a useful feature, that many people would use if they knew about it. If I didn't think it was useful, by far the simplest way to get it out of the patchqueue would be to simply remove the functionality from the next release of XenServer. I think the "wait for people to ask for it" won't work very well for this particular feature, because it's not the kind of thing I think most people would think to ask for. A bit like tmem -- I think it's a solution to a problem that people have that's very non-obvious, and must therefore be suggested to people rather than waiting for them to ask for it. I could write a blog post about it or otherwise try to promote the idea, but how many people are going to download a patch in order to try it out? (I'm aware the difference is that tmem's effectiveness can be measured with benchmarks while this feature cannot; I'm just saying that in both cases, you'd be waiting for a long time for people to demand it.) xenalyze will calculate and report domain runstate numbers based on vcpu runstate_change records, and I've found it useful to get a rough idea what's going on when I get traces in from the field. Of course there's no rush, but it's likely to be forgotten about for another two years. :-) (It's already been in the XS patchqueue since September 2008.) -George