On Mon, Jan 28, 2002 at 03:17:40PM +0100, Arni Ingimundarson wrote: > On Mon, Jan 28, 2002 at 04:06:16PM +0100, Paolo Mantegazza wrote: > > 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? > > I did not try it myself, but the claim worst case < 10us with avarage > about 5us. Someone even claimed he got about 2,5us.
Very hard to believe. Can you test? -- [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/
