Virtual Desktops on PCI-E SSD – Getting the image ready

One of the great things about VDI is the ability to create a ‘golden image’, that’s one single image that includes the OS and Software which can be accessed from any endpoint. Whatever VDI software you go with will then take that golden image and duplicate it multiple times to provide the desktops for your users.

However this masse creation of desktops can cause a bit of a IO overload…..one problem of many that a SSD can solve….

The screenshots below shows the top performance (from the 4x15k SAS array and the SSD) seen when 20 desktops are being created.

As you can see the SSD is the clear winner in bandwidth but more notably disk response times and disk queue length when it completely trounces the HDDs slowest response time of 266ms with a mere 21ms and the high disk queue length of 27.91 with a queue length of 1.53.

The scores on the doors shows that it took a whole 6min 30s to get the first desktop ready on the HDD based test and a similar 6min 15s on the SSD; the real difference comes in how long to get all the desktops ready with the HDD scoring 42mins and 13s to get all 20 desktops ready with the SSD getting it done in 19mins and 12s.

With the SSDs ability to randomly read/write lots of data at the same time I would also like to imagine that when creating larger numbers of desktops that the time difference between HDD and SSD would increase exponentially.

To finish off and as a little fun the image to the right shows the SSD doing a sequential read/write as it takes a testing desktop image and turns it into the finished article…ever seen 600MB/s from just a single drive?