Il 02/11/2012 04:10, David Gibson ha scritto: > Asking for some advice on the list. > > I have prorotype savevm and migration support ready for the pseries > machine. They seem to work under simple circumstances (idle guest). > To test them more extensively I've been attempting to perform live > migrations (just over tcp->localhost) which the guest is active with > something. In particular I've tried while using octave to do matrix > multiply (so exercising the FP unit) and my colleague Alexey has tried > during some video encoding. > > However, in each of these cases, we've found that the migration only > completes and the source instance only stops after the intensive > workload has (just) completed. What I surmise is happening is that > the workload is touching memory pages fast enough that the ram > migration code is never getting below the threshold to complete the > migration until the guest is idle again. > > Does anyone have some ideas for testing this better: workloads that > are less likely to trigger this behaviour, or settings to tweak in the > migration itself to make it more likely to complete migration while > the workload is still active.
Have you set the migration speed (migrate_set_speed) to something higher than the default 32MB/sec? Paolo