Hello!
On Wed, Dec 21, 2011 at 12:02:04PM +0100, Ivan Voras wrote:
> I have a strange situation on a VMWare 5-hosted machine:
>
> # vmstat -i
> interrupt total rate
> irq1: atkbd0 74 0
> irq6: fdc0 11 0
> irq15: ata1 17 0
> irq18: em0 42122 1
> cpu0:timer 2246291 54
> irq256: mpt0 141402 3
> cpu1:timer 280800 6
> Total 2710717 65
>
> The cpu0 timer interrupt rate is 54 Hz and cpu1 rate is 6 Hz. The
> same is visible when monitoring the system in real time with "systat
> -vm".
>
> This is a default FreeBSD 9 RC3 amd64 system, HZ is the default 100.
> Unless the tickless kernel project has advanced more than I think,
It is, actually. Many thanks to mav@ for his amazing work.
$ sysctl kern.eventtimer.periodic
kern.eventtimer.periodic: 0
$ vmstat -i | grep timer
cpu0:timer 72769640 47
And down to 37 i/s as seen in "systat -vm". Idle virtual machine
now takes 2 times less CPU on my laptop as seen from the host.
> this looks like a problem... so I looked elsewhere and it turns out
> I cannot get more than about 55 interrupts/s with the disk
> controller either.
Happily goes to 6k i/s here (though it's under VirtualBox and
a bit old -current, not 9.0).
(Just in case: note that vmstat report rate since boot, "systat -vm"
may be better to look at current values.)
> Any ideas? I have another host running VMware 5 but only an 8-stable
> machine in it, which works fine. Does anyone else run 9.x on VMware
> 5?
>
> The host is a Xeon X3360 CPU (4 cores, no HTT, 2.8 GHz).
Maxim Dounin