From mboxrd@z Thu Jan 1 00:00:00 1970 From: Frank Rowand Subject: Re: real-time priority Date: Thu, 19 Mar 2009 16:26:22 -0700 Message-ID: <49C2D49E.2010900@am.sony.com> References: <49C2CAFB.5030702@lavabit.com> <49C2D117.9070501@lavabit.com> Reply-To: frank.rowand@am.sony.com Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Cc: linux-rt-users@vger.kernel.org To: Rodrigo Amestica Return-path: Received: from outbound-sin.frontbridge.com ([207.46.51.80]:54575 "EHLO SG2EHSOBE002.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754365AbZCSX0v (ORCPT ); Thu, 19 Mar 2009 19:26:51 -0400 In-Reply-To: <49C2D117.9070501@lavabit.com> Sender: linux-rt-users-owner@vger.kernel.org List-ID: Rodrigo Amestica wrote: > yes, i forgot to include the link. now it goes. > > http://www.ddj.com/linux-open-source/200900827 > > Rodrigo Amestica wrote: >> Hi, >> >> general questions from somebody who's just starting to look into the >> preempt patch. >> >> the article linked below makes direct reference to the behavior of the >> preempt rt patch. The article was written in 2007. How much of that >> still holds true in the current version of the patch? >> >> I'm basically wondering about the first sentences in the abstract of >> that article. The big picture seems to be rather simple: calls to >> specific linux services could break the performance of a real time >> task by depending on lower priority tasks to complete that service. >> >> Does this mean that one must always be alert to which system services >> are invoked during the execution of a real time task? Yes. >> Does the vanilla >> kernel or the preempt-rt patch tries to somehow detect this condition >> and alert somehow? I am not aware of any such test, but it sounds like an interesting idea. >> >> thanks, >> Rodrigo >>