On Mon, Mar 28, 2011 at 7:32 PM, Jes Sorensen <jes.soren...@redhat.com> wrote: > On 03/28/11 18:25, Clemens Kolbitsch wrote: >>> Hi Clemens, >>> > >>> > Could you clarify what you are doing, when you say snapshot do you mean >>> > a savevm operation (ie. checkpoint) or a disk snapshot? >> I Jes, >> >> sorry for not being clear: I use a savevm operation. >> >> Following setup: I have a base file (qcow2 or qew format) and a snapshot file >> (generated via 'qemu-img create -b <basefile> -f qcow2 <snapshotfile>') and >> boot the snapshot file. Once the system (WinXP SP3 guest) has fully started, >> I >> create a snapshot (savevm <foo>) and exit the emulator. Later, I resume the >> snapshot by starting Qemu with the snapshotfile and say 'loadvm <foo>'. >> >> Actually, I found that the times I gave in my last email were way >> underestimated. The time difference is MUCH larger than 2-3 seconds per day. >> A >> week-old snapshot can take minutes to load on a reasonably idle host machine. > > Ok, then I am pretty much in the dark on this one - I don't know > anything about the checkpoint/restart feature and the impact on things > like the clock. I only worked on the live snapshot code (for disk > snapshots). > > Hopefully someone else will have an idea.
Sounds like a bug in the RTC. Maybe decoalescing is triggered, which would cause a burst of RTC interrupts to catch with the system clock?