Arni Ingimundarson wrote: > > Hello, > > I was asked to demonstrate RTLinux to research group at the university > (TU-Darmstadt). They are now using proprietery RT OS. > > All wenn well and we had usually about 5us irq latency. The problem > was every now and then the latency got as high as 20-25 micro seconds. > > That is way to much. > > I was running this on a Intel Celeron 300A with ISA timercard giving > interrupt and the IRQ-handler sending one pulse to the Parallel-Port. > RedHat 7.2 with RTLinux 3.1 on Kernel 2.4.4 and KDE. (I know ISA isn't > the best for RT but it shouldn't matter with this test). > > My question is: Is it known what programs/tasks could be blocking > interrupts? Wouldn't it be possible to not run those programs to > guaranty shorter responce time ? > > I would apreciate any info.
The real question is: what do the proprietary OS they use attain on the same hardware for the same test? Note that those 20 us are not so bad and are there to stay for ever. They can disappear just if you can spoil your system of anything and use very fast, likely non ISA, cards. Paolo. -- [rtl] --- To unsubscribe: echo "unsubscribe rtl" | mail [EMAIL PROTECTED] OR echo "unsubscribe rtl <Your_email>" | mail [EMAIL PROTECTED] -- For more information on Real-Time Linux see: http://www.rtlinux.org/
