From: "Jan Beulich" Subject: Re: [PATCH][RFC] remove PV/x86 warnings (timewentbackwards) Date: Thu, 11 Dec 2008 11:12:32 +0000 Message-ID: <494103B0.76E4.0078.0@novell.com> References: <4940FA1F.76E4.0078.0@novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: Content-Disposition: inline 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: Atsushi SAKAI , xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org >>> Keir Fraser 11.12.08 12:03 >>> >On 11/12/2008 10:31, "Jan Beulich" wrote: > >>> That might be considered skirting around the problem. Are users still = seeing >>> this with xen 3.3 and xen unstable? >>=20 >> Unfortunately yes, but rather seldom these days. We just got a fresh >> report about a larger IBM system suffering from it - while the initial = report >> they sent had hundreds of milliseconds in them, the most up-to-date >> one we have shows that it's just a few milliseconds above the -10ms >> boundary. So far I haven't been able to figure what causes this. > >Perhaps we should expand the default acceptable jitter a bit? Still, I'd >hoped that 10ms would be plenty! So would I (and really I find 10ms pretty wide already), which is why I never proposed an adjustment here, despite getting reports about these messages popping up every once in a while. And then again, it's configurable on the command line and via sysctl, so if someone really just wants the messages go away, he can already do that. Jan