Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I am running 4 virtual machines on my external hard disk (USB 2.0, 5400 rpm, Western Digital). Yesterday I wondered with they are running to slow but i am not sure from which fact makes it slow:

  • USB 2.0
  • 5400 rpm

Do you think the performance will more increase if I switch to an USB 3.0 disk or to a 7200 rpm external hard disk?

share|improve this question
Were you running all 4 VMs at once, or invdivually? If you run all 4 VMs from an internal drive, on the same system, do they perform any better? Was this configuration 'fast' for you in the past? – Ƭᴇcʜιᴇ007 Jul 29 '11 at 13:05
I'm running approximately 4 VMs at once. It depends on which server I need. But I found an option which increases the speed of my VMs: mainMem.useNamedFile="FALSE" – mhp Aug 1 '11 at 17:39
up vote 1 down vote accepted

Easy. It is the hard drive. Hence it is a 5400RPM drive, it's a simple laptop drive which won't perform very well in any situation. They are made to save power.
Get a 3.5" closure, and a WD Caviar Black hard drive.
OR if you can't buy a new closure, get a 2.5" WD Black Scorpion.

Both hard drives are cheap, and designed to be perform very well in a desktop environment / demanding situation. Personally I use both. Caviar in my desktop, and Scorpion in my laptop. Both are blazing fast. (On my laptop, I didn't notice any overheating/too much heat after installing the HDD.)

NOTE: I'm not a WD fanatist, or whatsoever. I just couldn't find any other hard drives designed to be like this. Only found simple, normal ones. If you know about any "high-performance" HDDs at other manufacturers, just link them / modify my answer please.

About the USB2 interface: If you buy a new closure, you will have a 3.0 closure anyway. However, if you keep the one you have now, don't bother about the interface. It only matters if you keep copying straight. Like a huge VM file. If you just work on it, run your VMs, it won't matter.

share|improve this answer

Having datastores on a USB-connected disk is going to give horrible performance, whatever the USB interface spec - mostly due to the way disk swap files are used for memory management. If you're changing things, go for an eSATA enclosure and get yourself an eSATA adaptor for the computer if you need one.

A bit more info here:

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.