VirtualBox on OSX: host unbearably slow

Question

Even though my mac is quite new and well equipped, using virtualbox slows it down to a crawl. Here's an example:

With Virtualbox open, running a Windows XP guest:

➜  uptime
 9:19  up 2 days, 17:28, 1 user, load averages: 1.97 1.64 1.59

A few minutes after closing Virtualbox:

➜  uptime
 9:21  up 2 days, 17:31, 1 user, load averages: 0.68 1.23 1.42

My Mac is a MacBook Pro 9.1 2.3 GHz Intel i7 with 8 cores, 4GB of RAM, a 500GB 7200 RPM disk running OSX 10.8.4.

The Windows XP host is configured to use 1Gb of RAM and only one core.

Note that running the same virtual machine from a trial version of Parallels is very smooth. I tried meddling with the guest settings (PAE settings, etc.) to no avail.

The virtual machine usage per se is OK, it's the application switching that is extremely slow. I'm talking 15-20 seconds to change app - with lots of disk use.

[edit]

Here is the memory usage before opening VirtualBox and while running the VM:

And htis is after a sudo purge:

Note that after the purge, the system became much more usable. Is it just memory then? How can I improve on this situation?

Answer 1

I had the same issue with running a guest Ubuntu on a host Windows 10 machine. The problem turned out to be a clipboard program called "Ditto", which was installed on the host Windows machine, somehow interfering with Virtualbox, causing the host to slow to a crawl. Perhaps you're in a similar situation where multiple programs are interfering with each other.

I fixed my issue by exiting Ditto.