Hi Michael,

Thanks for taking a look!  Ah I see, I thought that refining on the PID of a process only filtered the buffer to show the process and it's direct children but looking at 'proced-filter-children' this doesn't appear to be the case.

I've attached a patch which changes the refinement tests to use the simpler CPU refinement behaviour (keep everything with %CPU >= process at point), which appears to work well.

On the downside, whilst running the new tests I noticed an occasional flake with the 'proced-update-preserves-pid-at-point-test' test.  Unfortunately I still can't find the root cause after debugging it for a while so I've marked it as unstable in the patch for now as well.

Thanks, Laurence