We’ve included some really neat performance counters that you can use to monitor PNRP.  If you’re an application developer, you might use these performance counters to evaluate what impact your use of PNRP will have on the system as a whole.  They're also an interesting debugging aid when things go wrong.

To view these counters, open up perfmon (start > run > perfmon.msc).  Click on the “Performance Monitor” choice under “Monitoring Tools” in the left hand pane under the heading “Reliability and Performance.”  You should see a graph measuring CPU usage over time.  You can add the PNRP counters to this graph by right clicking the image and selecting “Add Counters…” from the menu.

The PNRP performance counters can be found under the heading “Peer Networking Resolution Protocol.”  On Vista / WS08 there are five of them.  Select the counters you’re interested in, and then click the “Add” button.  After clicking “Ok” you should return to the original graph which now includes PNRP metrics.

The five counters are…

Bytes received/sec:  the number of bytes received by PNRP in the sampling interval (1 second).

Bytes sent/sec:  the number of bytes sent by PNRP in the sampling interval (1 second).

Number of IDs registered: the number of names registered by all processes on the system.

Number of resolves:  incremented each time an application initiates a PNRP name resolution.

Stale cache entry hits:  incremented each time PNRP attempts to contact an unresponsive node when doing internal cache maintenance or when resolving a name.

It’s important to note that the PNRP performance counters report the cumulative results from all clouds.  If you publish a name in both the link local, and Global_ clouds, PNRP will use some on-link bandwidth and some internet bandwidth maintaining the names.  If your ISP limits your bandwidth every month, you might be interested in PNRP internet bandwidth usage, but you probably don’t care about the on-link bandwidth use which never makes it to the ISP.  Unfortunately, the PNRP performance counters lump it all together.

Have fun!