On the Parallel Processing Factor environment documentation, it reads:
Tools that honor the Parallel Processing Factor environment will divide and perform operations across multiple processes.
It is unclear which tools these are. Is there a list of such tools? I ran a hex grid script over a large area using Generate Tesselation and while it didn't give me any feedback on using a parallel processing factor, only one of my cores out of 36 was used to complete the job.
if you scroll to the very bottom of the help topic for that page you will see
Hi Eric Eagle
In regards to a list of tools that support parallel processing, we do not have one that is public yet. I just wrote one and hopefully it can be made public soon, but in the meantime there is a method where you can find most of the tools that support the Parallel Processing Factor environment setting.
Please note that this will list most of the tools that support this environment setting. Some toolboxes such as GeoAnalytics Server and Raster Analysis will not be listed here, but can utilize distributed computing on your server machine.
Hope this helps,