Speed up your Multicast Deployment

Have you noticed that HPC Server 2008, in the default configuration, uses less than 10% of the bandwidth (on a Gigabit NIC) when sending multicast images on the private network? Just look at the network utilization in Perfmon during a deployment to see what I mean.

Punch it up
Here is an undocumented tweak that can increase the network utilization and speed deployment.

Registry Disclaimer:
If you edit your registry without backing it up, you could cause worldwide famine, gaps in the space/time continuum and potentially catch an STD.

On the Head Node, Edit this Registry key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WDSServer\Providers\WDSMC\Profiles\Custom\TpCacheSize


Edit FROM 1190 TO 11,190 (Decimal).


Then Restart WDS Server Service.

You may need to experiment with other values between these numbers to prevent swamping your private network.

This tweak is undocumented and unsupported, so your mileage may vary. But my 3GB Compute Node WIM Image now multicasts in under 1 minute. That cut 10 minutes off my total deployment time!