From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <5055E244.4040101@web.de> Date: Sun, 16 Sep 2012 16:29:24 +0200 From: Jan Kiszka MIME-Version: 1.0 References: <1347634862.78737.YahooMailNeo@web29605.mail.ird.yahoo.com> In-Reply-To: <1347634862.78737.YahooMailNeo@web29605.mail.ird.yahoo.com> Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Subject: Re: [Xenomai] Context Switch with rtnet List-Id: Discussions about the Xenomai project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Franz Engel Cc: "xenomai@xenomai.org" On 2012-09-14 17:01, Franz Engel wrote: > Hi, > = > I've a little problem. I'm using the rtnet.h-header and the following fun= ction: > ret =3D recvfrom ( ethernetConnection.sock, &recBuffer, sizeof ( recBuffe= r ),0, ( struct sockaddr * ) ðernetConnection.dest_addr,&destlen ); > = > = > I compiled the program with the xenomai compiling flags and library. > = > When I look to the xenomai state I get something like this: > CPU PID MSW CSW PF STAT %CPU NAME > 22 0 0 834840 0 00000082 0.1 rtnet-stack > 22 0 0 1 0 00000082 0.0 rtnet-rtpc > 0 6262 2 2 0 00300380 0.0 qs_robotpositio > 2 6265 2 6 0 00300380 0.0 qs_robotpositio > 0 6266 1 1 0 00300380 0.0 robotrsiinterfa > 1 6268 1147 2365 0 00300182 0.8 robotrsiinterfa > = > You can see, I get a lote of context and module switches just as the rtne= t-stack itself. Is that normal? Well, I have no clue what you configured, so I can only guess. If your task 6268 is a pure RT task that is not supposed to interact with Linux services, you first of all have a bug in your software stack. You should look for the reason of those mode switches to Linux, e.g. by asking Xenomai to raise SIGXCPU when this happens. Regarding the rtnet-stack context switches: basically, every switch is one packet arriving at your NIC. Either you are receiving a lot of small but valid packets or you are on an open network, and that is basically heavy unrelated broadcast traffic of other sources than the RT device(s). Jan -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 259 bytes Desc: OpenPGP digital signature URL: