Improving Disk I/O for Virtual Machine Demo and Test

If you are like me and work primarily on a notebook computer, having the best performing system for demos and testing can save you time...and since time is so critical to work life balance, wasting time waiting for virtual machines to load, run and shutdown is a waste of valuable time.

If you have not realized this yet, having your virtual machines on a disk separate from the system disk will give much better performance.  Most people use the readily available USB or FireWire attached external disks.  USB 2.0 runs at 480 Mb/sec and FireWire runs at 400 Mb/sec. USB places additional load on your computer processor, FireWire has its own processor. I will stay away from the argument which one is better, because they are both slowpokes compared to the latest technology...keep reading.

ExpressCard is a new expansion card interface standard that the latest notebooks include. ExpressCards operate at 2.5 Gb/s, over 5x faster than USB or FireWire. Check out your notebook to see if you have an ExpressCard interface. The ExpressCard standard is only 34 mm wide (about 2/3 the with of a standard PCMCIA interface).  You machine might have a 34 mm wide slot or it might have a 54 mm wide slot that the 34 mm port is on one side.

So how does this help me you ask?  Combine an ExpressCard slot, an ExpressCard that supports the external SATA (eSATA) interface, and an external SATA II disk in a case with an eSATA port and now you have a disk system with about 5x the speed of what you might be using today.

Most eSATA ExpressCards that I have found using the Silicon Image ( chipset SILI32. This chipset supports two ports in RAID and non-RAID configuration.  I have used two cards on my notebook, one made by SIIG ( and one from Addonics ( with success.  I have used them with Vista (32 and 64) and Windows 2008 (64 bit) with no issues.

With Vista, you insert the card and the driver is installed automatically from Windows Update. With Windows 2008 you will need to go download the 64 driver from the manufacturers site.

Combine this with the new 7200 and 10,000 RPM drives and you have a sweet super fast external disk subsystem.  You can connect single drives to each port, RAID single drives across the ports on a single card or use an external disk cabinet with port multiplier support to connect multiple drives to a single port.  If you want to lug it around, you could have a 4 disk external cabinet configured as RAID 10.

Now if I could just boot from this device...;-)