On Thursday 16 February 2012 08:55 pm, Julian Elischer wrote: > kern.timecounter.tick: 1 > kern.timecounter.choice: TSC-low(1000) i8254(0) HPET(950) > ACPI-fast(900) dummy(-1000000) > kern.timecounter.hardware: ACPI-fast > kern.timecounter.stepwarnings: 0 > > switching the machine from TSC_low to ACPI-fast fixes the problem. > > in 8.x it used to default to ACPI > but I used to switch it to "TSC" to get better performance. > > I wonder why TSC-low is now bad to use.. > maybe the TSCs are not as well sychronised as they were in 8.x?
Can you please show us verbose dmesg output? FYI, TSC and TSC-low are not very different. TSC-low is just lower resolution version of TSC for SMP. Only difference is, we have automated your timecounter choice, i.e., if TSCs seem reasonably well-synchronized, select it by default but give lower resolution. In other words, if your TSC timecounter was never going backwards previously, TSC-low timecounter won't, guaranteed. So, the root cause should be somewhere else. Jung-uk Kim _______________________________________________ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"
