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I am using Windows 7 in VMWARE Workstation 7.1

When I try to delete a large folder of over 400 MB in size it takes more than half an hour. But when I do the same thing outside of VMWARE on my Host (also windows 7) it takes only a few minutes.

I have tried using SHIFT-Delete to skip the recycling bin, I tried sending to recycling bin, but they all have the same results.

It baffles my why it would take so much longer in VMWARE when it takes only a few minutes in the host.

I can understand if it took mabye 5 minutes longer than in the host, but it takes 28 minutes longer!

Anyone else experience this? Otherwise my VM runs fine and very responsive, only when removing large folders like this it takes forever.

Anyone know of a workaround or a fix?

screen shot

EDIT: A bit more information. It appears if I drop into command prompt and just run

del *.* /f /s /q

It completes within just a few minutes. So how come this works so much faster than deleting through windows GUI ??

share|improve this question
very unusual - I'm also interested to hear the answer to this... do you have VMware Tools installed on the guest? Where is the VM's drive? Is it on a USB key or external harddrive, or is it on the host's main drive? – warren Oct 5 '10 at 21:34
@Warren THe VM is on the host's main drive. Not RAID-ed or anything. VMWARE tools installed, latest version. Verified by checking for updates. 8 Gigs of RAM, of which is about 4 Gigs allocated to the guest. – 7wp Oct 5 '10 at 22:01
up vote 1 down vote accepted

You're getting hit by random access time slowness. Deletes are inherently random access loads. Unfortunately, unless you built your VM with a thick provisioned disk, which is not the default, every read or write needs to be translated by VMware into an actual location, because the hypervisor doesn't waste time storing unused space on the guest.

You might achieve slightly better results by defragmenting the VM (note: not to be confused with Windows' defragmentation, this is defragmentation of the VMDK format itself), which is accessible by shutting down the VM, selecting the hard disk in the VM properties, and selecting Tools -> Defragment.

Note that if your VM has snapshots, only leaf snapshots (that is, those which have no snapshots of their own) will be able to be affected this way. Chunks of data on the snapshotted VMDK file won't actually be optimized.

Also note that if you are using snapshots, you're probably actually forcing VMWare to allocate more sections in the snapshot VMDK, because the deletes in those cases actually result in copying of new data, because the snapshot system is a copy on write environment in that scenario.

In general, disk performance is not a major plus of using VMs :(

share|improve this answer
Billy, do you think if I provision a thick disk and then transfer the OS onto the new disk will it have noticable improvement? Is it worth my time to try that, or will the performance gain be minimal? – 7wp Oct 5 '10 at 22:05
@FooBook: It might help... can't hurt by trying it though, right? – Billy ONeal Oct 6 '10 at 18:10

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