# What do the elements of the Parallel Kernel Status screen mean?

I just managed to get my multiple kernels up and humming on a new multi-core machine, which I am quite happy about.

I am slightly at a loss, though, about the meaning of the different parts of the Parallel Kernel Status monitoring screen, as the official documentation on it is quite sparse.

This screen is accessible from the Evaluation menu. Clicking on Select Columns... goes some way into clarifying some of the more mysterious elements:

In particular

• CPU gives the CPU time used so far by that kernel, and
• RAM gives the RAM it's currently using.
• The dots change color from green to red when a kernel starts calculation and back to green when it finishes.

However, I have a few specific questions:

• What does the Time column measure?
• What does the Elapsed dialog measure?
• What exactly is the speedup? What is it comparing with?
• What are the green bars? Upon mouseover they grow tooltips with percentages with no indication of what they are. For the ones above I imagine the kernels are not really being used to their full potential; is that the case? (And, if so, is there a good resource for ideas on fixing that?)
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