From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4F69156D.3060005@domain.hid> Date: Wed, 21 Mar 2012 00:40:29 +0100 From: Gilles Chanteperdrix MIME-Version: 1.0 References: <623784B6C75D274389918D358E89E8BB0B78F111@domain.hid> <4F6897A5.70601@domain.hid> In-Reply-To: <4F6897A5.70601@domain.hid> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [Xenomai-help] How do I increase CPU time limit. List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Philippe Gerum Cc: "xenomai@xenomai.org" On 03/20/2012 03:43 PM, Philippe Gerum wrote: > On 03/20/2012 03:09 PM, Chris Stone wrote: >> I have a thread which uses a lot of CPU and it is receiving a SIGXCPU: >> Cpu time limit exceeded. Does this message really mean I have exceeded >> some CPU time limit? If so, how do I increase or disable the CPU time >> limit? The code that I am running has been working for quite some time >> under regular Linux and I have just ported it to Xenomai, so I doubt >> there are any infinite loops in it. > > This could be the runaway thread detector triggering, after 4s of > uninterrupted runtime (which is huge, is this intended?). This is a > debug mechanism Xenomai implements to recover from a runaway thread > chewing CPU in primary mode, without having to resort to the reset button. > You can either extend the grace period above the default 4s, using > CONFIG_XENO_OPT_WATCHDOG_TIMEOUT, or disable the watchdog entirely by > switching off CONFIG_XENO_OPT_WATCHDOG. This said, 4s is really long > already, so the regular kernel might not cope with even more starvation > from normal interrupts. > > Other explanation would be not time-related. If > CONFIG_XENO_OPT_DEBUG_SYNCH_RELAX is enabled, any attempt to switch to > secondary mode while holding a real-time (Xenomai created) mutex in the > code would trigger such signal, as a warning to point out a priority > inversion. You may find an example of how to install a SIGXCPU handler and decode signals sent by xenomai in examples/native/sigdebug.c -- Gilles.