From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4BEBC119.4070408@domain.hid> Date: Thu, 13 May 2010 11:06:33 +0200 From: Jan Kiszka MIME-Version: 1.0 References: <4BEB0A05.5020006@domain.hid> <4BEB0EF2.7020604@domain.hid> <4BEB1C06.7030907@domain.hid> <4BEBB838.2080407@domain.hid> In-Reply-To: <4BEBB838.2080407@domain.hid> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig1E024B8FC3B7D78D5FB92A47" Sender: jan.kiszka@domain.hid Subject: Re: [Xenomai-help] native kernel task example List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: ramoncostacastello@domain.hid Cc: xenomai@xenomai.org This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig1E024B8FC3B7D78D5FB92A47 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Ramon wrote: > Hi, >=20 > I have a system developed (teaching and research purposes) developed in= > RTLinuxfree and currently I'm trying to migrate > this system to Xenomai (several task periodical task with period of > 100us (one at 50us)). > As a first step I would like to run them at kernel level to preserve > performance (hard realtime), Unless your system is already running on its limits with this 20 KHz job, kernel vs. user space won't make the big difference. Check the results of the latency test while loading the system with I/O and memory cache stress to get a first impression. > latter I will try to migrate > user space. Specifically while trying to stabilize the port, you will quickly love the robustness of user space: if something crashes or hangs, just attach gdb - but don't forget to enable the Xenomai watchdog in order to catch runaway tasks. >=20 > This task contains low level commands (out, in commands to access AD/D= A > card registers) iopl(3) will grant your root user space process in/out privileges. Not nice, but probably easier as a first step than porting over the Analogy framework. Jan PS: Specifically for educational purposes, it is a bad idea to continue spreading the legacy concept of kernel-based RT applications. --------------enig1E024B8FC3B7D78D5FB92A47 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iEYEARECAAYFAkvrwRwACgkQitSsb3rl5xS8vACeMjGPoYDxFQh81cPfTYQ6cXXE mo8AnR8lBgoemx/G9G5IPEiEkTduPpPf =vBKb -----END PGP SIGNATURE----- --------------enig1E024B8FC3B7D78D5FB92A47--