From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Sigler Subject: Re: Old -rt patches Date: Mon, 06 Aug 2007 10:55:44 +0200 Message-ID: <46B6E210.9090502@free.fr> References: <46B0B7A4.8060805@free.fr> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: linux-kernel@vger.kernel.org, mingo@elte.hu, tglx@linutronix.de To: linux-rt-users@vger.kernel.org Return-path: Received: from smtp4-g19.free.fr ([212.27.42.30]:53442 "EHLO smtp4-g19.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756783AbXHFIzs (ORCPT ); Mon, 6 Aug 2007 04:55:48 -0400 In-Reply-To: <46B0B7A4.8060805@free.fr> Sender: linux-rt-users-owner@vger.kernel.org List-Id: linux-rt-users.vger.kernel.org John Sigler wrote: > I wrote a Linux app where I need high-resolution timers. I went all the > way and installed the -rt patch, which includes the -hrt patches, as far > as I understand. > > Since I could not afford to change kernels with every new release, I > decided to track the 2.6.20 branch (arbitrarily). > > At this point I'm using 2.6.20.7-rt8 (-rt8 was the last patch to the > 2.6.20 branch). (I see 2.6.20 is already up to .15) > > I see a lot of patches going into the -rt patch, but development moved > on to 2.6.21, then 2.6.22, and now 2.6.23, following mainline. > > I'm not a kernel hacker, so I don't claim to understand the patches, but > the comments sound like a few bugs are fixed here and there. I can't > tell whether these bugs also exist in previous kernels or only appeared > in newer kernels. Even if I knew, I probably wouldn't have the expertise > to back-port the patch. > > I'm seeing weird behavior in my app, when it has been running 2-4 days. > The timers start to act out, and all hell breaks loose. Basically, I > have no idea what's going on... > > My question is: is it possible that there is a bug in 2.6.20-rt8 that > has been fixed in subsequent -rt patches (there's a 2.6.21.6-rt21 and a > 2.6.22.1-rt9)? In other words, if I give 2.6.21.6-rt8 or 2.6.22.1-rt9 a > spin, is it possible that my weird behavior disappears? > > I'm not saying that it's impossible for the bug to be in my app, but the > app is small enough that I'm fairly confident there's no problem there. Would anyone care to comment? Perhaps I could also test a different strategy, such as xenomai? http://www.xenomai.org/ Regards.