Messages in this thread | | | Date | Thu, 22 Nov 2007 21:29:51 +0100 (CET) | From | Thomas Gleixner <> | Subject | Re: nohz and strange sleep latencies |
| |
On Thu, 22 Nov 2007, Pavel Machek wrote: > > but perhaps somehow we miss this fact and fail to turn off the lapic > > clockevents drivers? > > Ok, I guess I'm lost. If I offline second CPU, I immediately get > 1000Hz timer tick... is that expected?
Hmm. No. I have no idea why this is happening.
34196 total events, 55.083 events/sec echo 0 >/sys/devices/system/cpu/cpu1/online 36073 total events, 54.679 events/sec
> I'm trying to decide when system is idle (lets say that means "no user > task is scheduled to wakeup within 10 seconds)... I added some > instrumentation to nohz subsystem, but it does not behave like I'd > expect: even if I run "while true; do sleep .01; done" loop, I see > nohz preparing for 5 seconds sleep... while it seems obvious that it > can only be 10msec sleep, and with max_cstate=1, it works that > way... Plus, nte->start_pid seems to contain some random numbers :-(. > > What am I doing wrong? > > (Patch for illustration, I can generate full diff against vanilla, > but...)
Just to make sure what we are hunting: Do you have the same problem with an non-pavel-tainted 2.6.24-rc3 ?
tglx - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |