On Thursday 21 June 2007 08:06:14 you wrote: > Hi to all, > > Sorry for my poor english. > > 1) What are reliable clocksources? > Depends on a lot on your architecture, chipset, SMP vs. UP, etc. I have been testing mostly with the acpi_pm timer and having good results - there may be a better timer available on your particular system. Can you provide the contents of: /sys/devices/system/clocksource/clocksource0/available_clocksource and /sys/devices/system/clocksource/clocksource0/current_clocksource > 2) I have a mainboard with a 500 Mhz cpu which works perfectly with RT. > I suppose that the max resolution is 2 ns for the high resolution timers > but a "cat /proc/timer_list" reported: Note that timer resolution is not bound by CPU. There is also a difference between resolution and accuracy :-) So while you can set timers with nanosecond resolution, you will likely see expiration accuracy in something more like the tens of microsecond range. Regards, Darren Hart > > cpu: 0 > clock 0: > .index: 0 > .resolution: 1 nsecs <---- > > active timers: > clock 1: > .index: 1 > .resolution: 1 nsecs <---- > > How it is possible that this mainboard have 1 nsecs resolution? > > Excuse me if it are stupid questions. > > Thanks in advance! > > Ciao, > Alessio > > - > To unsubscribe from this list: send the line "unsubscribe linux-rt-users" > in the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Darren Hart IBM Linux Technology Center Realtime Linux Team - To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
