(Ubuntu 14.04 server, 8 cores, 16GB RAM)
When running 3 scripts in parallel that utilise the same (other) script, the inverse of what I expect to happen occurs when "renice-ing" the processes as they are running.
Those with higher niceness - i.e. lower priority, use more CPU
Those with lower niceness - i.e. higher priority, use less CPU
It remains (pretty much) like this throughout execution. Any ideas? Have I fundamentally misunderstood what niceness is?
(I also tried renice-ing the parent scripts but it didn't seem to make a difference.
sudo top had to be run to have permission to do all this.)
(Also I think the times can be ignored, as
3167 was the second
mgiza to be run by the parent - it originally had one with a lower PID)
Edit: All three of these processes are happy (and allowed) to go up to using 800% CPU!