It seems that VCPU system time isn't monotonic (using 3.0.4). It seems
it might be correlated to when a VCPU is switched across real CPUs but I
haven't conclusively proved that. But e.g.:
 {
 old = {
 time = {
 version = 0x4ec
 pad0 = 0xe8e0
 tsc_timestamp = 0x22cc8398b7194
 system_time = 0xe8e0345d8805
 tsc_to_system_mul = 0xd62c0083
 tsc_shift = '377円'
 pad1 = [ '002円', '027円', '365円' ]
 }
 result = 0xe8e0484568fa
 tsc = 0x22cc86921ab00
 cpu = 0
 }
 new = {
 time = {
 version = 0x4ee
 pad0 = 0
 tsc_timestamp = 0x22cc7db96cd29
 system_time = 0xe8e00d1031f3
 tsc_to_system_mul = 0xd62ae844
 tsc_shift = '377円'
 pad1 = [ '357円', '002円', '365円' ]
 }
 result = 0xe8e048456012
 tsc = 0x22cc869225443
 cpu = 0
 }
 delta = 0xfffffffffffff718
 }
>From what I can work out, time is supposed to be monotonic but I admit I
can't really understand the time code yet at least. I couldn't find any
documentation on what to expect from system time. Any suggestions?
This seems to happen across all the hardware we've tried but this
particular case is a Sun V20Z with two CPUs:
 x86 (AuthenticAMD family 15 model 5 step 10 clock 2392 MHz)
 AMD Opteron(tm) Processor 250
cheers,
john
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