An interesting new feature was included with the XenServer 7.1 release: Provisioning Services Accelerator.

In a single sentence,

PVS Accelerator overcomes PVS server and network latency by utilizing local XenServer RAM/Disk resources to cache blocks of a PVS vDisk to fulfill local target VM requests.

Take a look at the demo video to see:

A few things to note:

1. Network utilization drops significantly as target VM requests are fulfilled by the local XenServer Cache
2. Accelerator should help reduce retries as the network is not as heavily utilized
3. Any licensed version of XenApp/XenDesktop has access to this feature
4. VM boot time drops significantly.

I did some testing on the last point around boot time.  By enabling PVS Accelerator on XenServer 7.1, the boot times dropped by around 60%.

A very nice improvement with integrated technology.

Daniel (Follow on Twitter @djfeller)
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