We are suddenly experiencing very poor performance on some Hyper-V VMs.
Dell 2950, (2x) Xeon 3Ghz, 6x SATA drives 16G memory Server 2008R2..
All was fine until last week. Now the vms (several XP, one CentOS) are very uniformly slow to respond, and I can not track down the issue. No changes in vms for quite a while. Hyper-V monitor reports very normal (low) cpu use by vms. Performance monitor on host machine show low cpu/network/disk use, 43% committed bytes in use. In other words, nothing really unusual and the same stats as always. The only thing that may be differnt is that I did snapshot a machine last week, have done that many times before without issue.
Even just logging in on an XP vm that has been running nicely for a long time is problematic.
Suggestions on where to look next?