When I convert a disk from dynamic to fixed the performances of all other VM are very poor RRS feed

  • Question

  • Hi all,

    I've a 2 node cluster with Windows Server 2008 R2 SP1, on the top of the cluster there is Hyper-V and 10 virtual machines. I've experienced that if I try to convert a disk from dynamic to fixed (we are talking about a 100 GB disk) the operation is very slow (1 hour) but this is not a real problem. A real problem is that in the meanwhile all other virtual machine became very very slow in responding to simple mouse input via RDP sessions... is this behaviour by design?


    the storage is accessed by the nodes via MPIO and 4GB fibre channel HBA

    each node as 3 nic: 1 for Hyper-V, 1 for HB, 1 for LAN comunications

    Tuesday, August 2, 2011 10:14 AM

All replies

  • The disk convert is very intensive operation, I typically pull the machine to a local disk to do the convert, to keep from impacting everything else.  What RAID level is your storage?  I have found over time that RAID10 has the best performance for storing the VHD files.  I have also found that formatting the storage for VHD with 64K cluster size also helps.

    I would recommend the convert operation be done off the production server.

    Bill Chesnut | BizTalk Server MVP | Mexia Consulting | Melbourne Australia
    Please indicate "Mark as Answer" if this post has answered the question.
    Tuesday, August 2, 2011 11:54 AM
  • thank you for your reply, I will try with the 64k cluster size and see if this helps
    Wednesday, August 3, 2011 7:06 AM