I would like to be able to shrink or grow a virtual disk (with the obvious caveat of minimum required size for current data stored on it). Is this possible? In terms of performance and disregarding all other factors, which is the best virtual disk format (its on a 6-disk ZFS mirror, if that makes any difference)? TIA, Matt. -- This message posted from opensolaris.org
On Fri, Sep 4, 2009 at 10:47 PM, Matt<mailmattlaw@yahoo.co.uk> wrote:> I would like to be able to shrink or grow a virtual disk (with the obvious caveat of minimum required size for current data stored on it). Is this possible? > > In terms of performance and disregarding all other factors, which is the best virtual disk format (its on a 6-disk ZFS mirror, if that makes any difference)?Why not use zvol? AFAIK performance of a block device should be higher compared to file. Plus when you enable compression, zvol will store zeroes in a special way that uses no disk space, so if you set "refreservation=none", you can "defragment" by writing zeroes to unused disk space (like with sdelete for Windows domU). -- Fajar
Sorry, I''m still learning ZFS. Do you mean use a separate zvol on top of my mirror for each virtual disk? Would it then be possible to shutdown the domU, use ZFS to resize the volume and bring it back up again? Is it feasible to use OpenHA to create a redundant iSCSI storage cluster and have multiple hosts use that for their domUs? What is the performance like over iSCSI or NFS? - I imagine you would need gig ethernet or faster? Thanks, Matt. -- This message posted from opensolaris.org
On Fri, Sep 4, 2009 at 11:55 PM, Matt<mailmattlaw@yahoo.co.uk> wrote:> Sorry, I''m still learning ZFS. Do you mean use a separate zvol on top of my mirror for each virtual disk?Yes. Just like you''d have a separate file for each virtual disk.> > Would it then be possible to shutdown the domU, use ZFS to resize the volume and bring it back up again?Yes.> > Is it feasible to use OpenHA to create a redundant iSCSI storage cluster and have multiple hosts use that for their domUs? What is the performance like over iSCSI or NFS? - I imagine you would need gig ethernet or faster?Sorry, I''ve never use OpenHA. But in general, yes, you''d need gigabit or faster for acceptable performance. -- Fajar