I have added some server metrics output to the running controller script. This allows you to keep an eye on your test tool servers as the test is running. This can sometimes be crucial, especially with JMeter, which can be resource hungry.
In practice, in the modern world (!) CPU and Memory are often not as useful as they used to be. With VMs and hyperthreading CPU often isn't correct and Memory isn't so useful for java apps - it could be useful for native apps.
But average load (processor queue length) is useful, so I've reported it here. It could also be useful to plot gc stats for jmeter. This could be added by running jstat or similar over ssh - see below.
For this release, I print out the controller and injector load average for each screen output iteration: