<br><br><div class="gmail_quote">On Mon, Mar 3, 2008 at 2:01 PM, Robert F. Scheer <<a href="mailto:rfscheer@speakeasy.net">rfscheer@speakeasy.net</a>> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Also, after installing the linux-rt ("realtime") kernel from Ubuntu<br>
repositories, the delay bag performance was horrible, as mentioned<br>
earlier, but not in the same league of hurt as the results you've just<br>
posted.<br>
</blockquote></div><br><br>I can't tell if there's just the one real-time Linux which has multiple names or if they're separate projects; I'm seeing linux-rt, Linux/RT, rtlinux, RT-Linux, ...<br><br>Anyway, if they're all the same thing, then you're not using any of the real-time features:<br>
<br><a href="http://www.faqs.org/docs/Linux-HOWTO/RTLinux-HOWTO.html">http://www.faqs.org/docs/Linux-HOWTO/RTLinux-HOWTO.html</a><br><br>In order to get real-time performance, it sounds like you need to write your real-time code as a kernel module, and the rest of your application (the parts that don't need to be real-time) would run in user-land and communicate using a real-time FIFO character device.<br>
<br>Also, by real-time, they really do mean real-time: "<font face="Arial,Helvetica" size="3">Worst case interrupt latency on a 486/33Mhz PC measures well under 30 microseconds, close to the hardware limit." (ref: <a href="http://www.linuxdevices.com/articles/AT3694406595.html">http://www.linuxdevices.com/articles/AT3694406595.html</a>, assuming it's the same RT-Linux).</font><br>
<br>Gulik.<br clear="all"><br>-- <br><a href="http://people.squeakfoundation.org/person/mikevdg">http://people.squeakfoundation.org/person/mikevdg</a><br><a href="http://gulik.pbwiki.com/">http://gulik.pbwiki.com/</a>