Hi
We're dealing with a strange problem regarding disk performance issue inside VM running on a 3 node Hyper-V 2.0 cluster connected to HP EVA 44xx storage system.
We analized performance on EVA, Hosts, VM and came to the following clues:
- running about 10 VM there is no perofrmance issue. All VM have dynamic disks, capacity between 50-150GB (disk R/W is between 50-70MB/s)
- running 3 virtual machines with dynamic disks capacity 400GB or more there is a huge impact on disk performance (disk TR/W is between 10-15MB/s)
We did shut down on all VM on all nodes, and start-up only one VM that has 400GB vhd drive (inside VM there are two partitions on Windows 2008 system 50GB and data 350GB). We also stop all services running on this VM so that VM is actually idle, but disk performance is still 10-15MB/s.
This happens on all 3 VM with virtual disk 'large' vhd (about 400 or 500 MB).
On the other hand, running identical VM with 150GB vhd performance is 5x better.
HP found no problems with storage, so we're quite sure that there must be some kind of a bug or issue with VM or Hyper-V 2.0 (we're running free version of Hyper-V Server 2008 R2).
Any ideas or clues how can we proceed next? Has anyone had the same problem with Hyper-V so that can give us additional data to proceed ?
Regards,
Miha