Interoperability Happens

Wednesday, September 08, 2010

VMWare help

Hey, anybody who’s got significant VMWare mojo, help out a bro?

I’ve got a Win7 VM (one of many) that appears to be exhibiting weird disk behavior—the vmdk, a growable single-file VMDK, is almost precisely twice the used space. It’s a 120GB growable disk, and the Win7 guest reports about 35GB used, but the VMDK takes about 70GB on host disk. CHKDSK inside Windows says everything’s good, and the VMWare “Disk Cleanup” doesn’t change anything, either. It doesn’t seem to be a Windows7 thing, because I’ve got a half-dozen other Win7 VMs that operate… well, normally (by which I mean, 30GB used in the VMDK means 30GB used on disk). It’s a VMWare Fusion host, if that makes any difference. Any other details that might be relevant, let me know and I’ll post.

Anybody got any ideas what the heck is going on inside this disk?

Thursday, September 09, 2010 7:40:35 AM (Pacific Daylight Time, UTC-07:00)

Do ou have "undoable" mode on in the disk? This basically means its keeping the old data AND the new data for each bit written so that you can go back. If you do not use this feature, it can be turned off in the settings while the VM is offline.

Todd Gardner

Thursday, September 09, 2010 11:09:32 AM (Pacific Daylight Time, UTC-07:00)

If you have a snapshot, remove it. Snapshots append changes to the disk so the disk can grow much bigger than the maximum size if you aren't careful.

Otherwise, there is no problem. When you delete data, vmware won't shrink the size of the disk. It just keeps growing until it is 120gb. So everything seems fine.

John Smith

Thursday, September 09, 2010 11:17:20 AM (Pacific Daylight Time, UTC-07:00)

@Todd-- where do I find "undoable mode" in the VMWare settings? I don't have "AutoProtect" turned on, if that's what you mean.

@John-- I don't have a snapshot, at least I never took a snapshot by hand. I don't see any snapshots listed in the VMWare menu, so I'm assuming no such snapshot exists--is there some way to check at the file level? The bigger issue is that I'm *not* deleting data within the host, it's just slowly creeping upward at the 2X rate.

Ted Neward

Thursday, September 09, 2010 1:03:22 PM (Pacific Daylight Time, UTC-07:00)

Take a look at the modifyhd --compact section (uses sdelete) in http://www.virtualbox.org/manual/ch08.html#vboxmanage-modifyvdi. This used to only work with VDI images, but I think VMDK files are now supported.

Bob

Thursday, September 09, 2010 1:03:32 PM (Pacific Daylight Time, UTC-07:00)

See the attached image. This is the configuration screen for your VM. Select the Virtual Disk and make sure it is "persistent".

http://honeypots.sourceforge.net/undoable.jpg

Todd Gardner

Comments are closed.