Tomasz Chmielewski wrote:
Avi Kivity schrieb:
Tomasz Chmielewski wrote:
Why do my guests show "Clocksource tsc unstable" on bootup?
Linux expects the tsc to be monotonic and to have a 1:1
correspondence with real time, which isn't easy to achieve with
virtualization.
But the clocksource is kvm-clock, so why does the guest probe tsc at all?
Good question. I don't know what the answer is. Maybe the scheduler
uses tsc for its internal clock.
I pasted a part of /proc/cpuinfo below.
I saw these with kvm-83 and kvm-84 (with cpufreq disabled, as it
perhaps can matter).
processor : 3
vendor_id : AuthenticAMD
cpu family : 15
model : 65
model name : Dual-Core AMD Opteron(tm) Processor 2212
stepping : 2
cpu MHz : 2000.000
cache size : 1024 KB
physical id : 1
siblings : 2
core id : 1
cpu cores : 2
fpu : yes
fpu_exception : yes
cpuid level : 1
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 rdtscp lm 3dnowext 3dnow rep_good pni cx16 lahf_lm cmp_legacy
svm extapic cr8_legacy
bogomips : 3993.03
TLB size : 1024 4K pages
clflush size : 64
cache_alignment : 64
address sizes : 40 bits physical, 48 bits virtual
power management: ts fid vid ttp tm stc
This cpu indeed has unstable tsc, but disabling cpufreq should have
fixed it.
Maybe we need to disable C-states as well?
--
error compiling committee.c: too many arguments to function
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