From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tim Sander Subject: Re: Beginner's questions on userspace latency Date: Fri, 22 Mar 2013 21:21:51 +0100 Message-ID: <2181419.yCSEbLiqDZ@virgo> References: <514CB285.4050100@nittka.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit To: Oliver Nittka , RT Return-path: Received: from lvps176-28-13-145.dedicated.hosteurope.de ([176.28.13.145]:43724 "EHLO lvps176-28-13-145.dedicated.hosteurope.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1422904Ab3CVUac (ORCPT ); Fri, 22 Mar 2013 16:30:32 -0400 In-Reply-To: <514CB285.4050100@nittka.com> Sender: linux-rt-users-owner@vger.kernel.org List-ID: Hi Oliver > I read through the RT wiki, but I'm still unsure on how to proceed from > here. Is there any way to determine what's causing the glitches? > Anything I could do to improve the realtime behavior of my application? Realtime has a lot to do with your computing hardware + the drivers. The worst driver determines your max latency. As you have not told on what hardware you are running it is hard to give some hints... other than do latency tracing if your hw is powerful enough. Also you might look at the nice latency charts from osadl.org. Find a similar system to yours and look at the worst latencies recorded. Also keep in mind that latency tracing needs some time. There are some recordings of talks available for example of Frank Rowand about latency tracing but they are probably a little bit dated as the don't acount to much for the much improved latency tracing infrastructure within the kernel. Good luck Tim