Ubuntu timing (unresponsiveness) problems on Turion64 X2

[Edulix]

The machine feels really slow and unresponsive and it seems related to timing problems with my CPU, which is an AMD Turion64 X2. I'm using Ubuntu 7.04 as the host and Windows XP SP2 as the guest SO.

This is what I get:

00:00:00.000 TM: u64DeltaPrev=-13260680356091 u64PrevNanoTS=0x003d3786df9b5251 u64NanoTS=0x003d2b776176f156 u64Delta=0x3d0900
00:00:00.000 TM: u64DeltaPrev=-13260692348318 u64PrevNanoTS=0x003d3786e0524ef4 u64NanoTS=0x003d2b776176f156 u64Delta=0x3d0900
00:00:00.000 TM: u64DeltaPrev=-13260700346642 u64PrevNanoTS=0x003d3786e0cc5a68 u64NanoTS=0x003d2b776176f156 u64Delta=0x3d0900
00:00:00.000 TM: u64DeltaPrev=-13260712349782 u64PrevNanoTS=0x003d3786e18381ac u64NanoTS=0x003d2b776176f156 u64Delta=0x3d0900

Lots (megabytes) of lines of this kind appear in /home/edulix/.VirtualBox/Machines//TecnovaLogs/ files. I have already 4 log files (the maximun stored) and one of them is of more than 20 megabytes.

Note that this doesn't happen always that I boot the guest, but when it starts then there's no way back. And the problem very frequently.

[Edulix]

Log file

[bird]

Something really strange is going on there. The log timestamps are complete weird. First it starts out with 3:40:57.076 - 3 hours and 40 mins since the application started - which is something I find rather hard to believe. Then it suddenly drops to 00:00:00.000 which I find very hard to explain, unless by chance we're hitting a very high number that happens to have the lower end as all zeros...

Anyway, both the VM and this log timestamp uses the same time source so at least there is some kind of consistency here. The time is jumping back and forth about 3:4 every so often.

I wonder if it could've been a compiler optimization issue that we've fixed since 1.4.0, that's currently my best guess. (It could also be a out-of-sync TSC issue, but I can't imagine how that could be.)