REGRESSION: vbox 4.1 virtual disk read/write operations are UNUSABLY slow

[matteo sisti sette]

I used to have a Windows 7 guest on a ubuntu 11.10 host with virtualbox 3.x and it worked fine.

Then I upgraded to VirtualBox 4.1 on the same host. I recreated an IDENTICAL virtual machine from scratch (because of the infamous broken-3D-driver issue which left me with a broken unrecoverable guest, and none of the method described in the manual and in the forum for fixin it worked) and I installed the same Windows 7 guest OS on it, from the same installation CD as my old guest. Everything is exactly the same as before: same guest, same host, virtual disk in the same physical location, same machine settings, only VirtualBox 4.1 instead of 3.x

Now the guest is unusably slow. The bottleneck seems to be reading and writing from/to the vdi. I'm not sure whether it's only writing, only reading, or both, I am under the impression it's mainly writing.

Whenever the virtual disk is working, the virtualbox process on the host is consuming 100% CPU, and every disk read/write operation in the guest takes ages. It's simply, plainly unusable.

[Frank Mehnert]

A VBox.log file of such a VM session is missing.

[matteo sisti sette]

I'm starting to doubt the bottleneck is really disk read/writing. I'm starting to be under the impression that just EVERYTHING is unusably slow. May it be because of the new gpu virtualization?

[Frank Mehnert]

You could try to disable 3D support. One limiting factor is also that you are running 64-bit guests on a 32-bit host. This will always be slower than 64-bit on 64-bit. However, the performance drop should be not dramatic.

[aeichner]

Please reopen if still relevant with a recent VirtualBox release.