Re: kvm guest: hrtimer: interrupt too slow

[Michael Tokarev <mjt@tls.msk.ru>]

Avi Kivity wrote:
> On 09/29/2009 03:12 PM, Michael Tokarev wrote:
[]
>> The thing is that after some uptime, kvm
>> guest prints something like this:
>>
>> hrtimer: interrupt too slow, forcing clock min delta to 461487495 ns
[]
> What happens if you use hpet or pmtimer as guest clocksource?

For all the guests I have handy, only 2 clocksources
are available: kvm-clock and acpi_pm.  The host itself
has hpet turned off because it itself had issues with
hpet, and after many tries we finally turned it off
(there were several long and painy threads on lkml
about this).

Dunno why pmtimer isn't available.

I tried switching to acpi_pm on a running guest (which
is still runnining in very slow mode), but that did not
make any difference - i.e., it did not become "fast"
again.

> Please post host /proc/cpuinfo.

Here's the cpuinfo from host (for last core):

processor	: 3
vendor_id	: AuthenticAMD
cpu family	: 16
model		: 2
model name	: AMD Phenom(tm) 9750 Quad-Core Processor
stepping	: 3
cpu MHz		: 1200.000
cache size	: 512 KB
physical id	: 0
siblings	: 4
core id		: 3
cpu cores	: 4
apicid		: 3
initial apicid	: 3
fpu		: yes
fpu_exception	: yes
cpuid level	: 5
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm 3dnowext 3dnow constant_tsc rep_good nonstop_tsc extd_apicid pni monitor cx16 popcnt lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs
bogomips	: 4814.78
TLB size	: 1024 4K pages
clflush size	: 64
cache_alignment	: 64
address sizes	: 48 bits physical, 48 bits virtual
power management: ts ttp tm stc 100mhzsteps hwpstate

It has cpufreq enabled (ondemand), but turning that off
does not change anything (that was the first thing I
tried, but AFTER the guest become slow).

Thanks!

/mjt