Messages in this thread | | | Date | Mon, 6 Jul 2015 10:51:05 -0700 | Subject | Re: [PATCH] clocksource: Allow toggling between runtime and persistent clocksource for idle | From | John Stultz <> |
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On Mon, Jul 6, 2015 at 8:46 AM, Thomas Gleixner <tglx@linutronix.de> wrote: > On Mon, 6 Jul 2015, Tony Lindgren wrote: >> * Thomas Gleixner <tglx@linutronix.de> [150706 07:20]: >> > On Mon, 6 Jul 2015, Tony Lindgren wrote: >> The timekeeping accuracy issue certainly needs some thinking, and >> also the resolution between the clocksources can be different.. In the >> test case I have the slow timer is always on and of a lower resolution >> than the ARM global timer being used during runtime. >> >> Got some handy timer test in mind you want me to run to provide data >> on the accuracy? > > John Stultz might have something.
You can turn on ntp stats in your ntp.conf and chart the loopstats data w/ gnuplot:
set terminal png set output "loopstat.png" plot "/var/log/ntpstats/loopstats.<dateoftest>" using 2:3 with linespoints
I also have the drift-log.py and graph-log.py scripts I use here: https://github.com/johnstultz-work/timetests
But those aren't really ready for mass consumption, as they're probably not very cross-distro compatible.
thanks -john
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