I am trying to figure out some details about reaper for a non-technical,
generic BSD article and maybe some manual pages about special system
processes. And I have a few questions.

I understand that the reaper is a kernel process thread that helps free a
dead process's VM resources, old stacks and u-area. Then the process
becomes a zombie.

Does vmspace and VM resources mean the same thing?

Does anyone have an example or an easy-to-understand description?

What does the following mean?
     "Give machine-dependent code a chance to free any resources it
     couldn't free while still running on that process's context."

What is "u-area" mean? How is it related to the reaper?

On a related note, are there any special system processes other than the
swapper, pagedaemon, reaper and ioflush?

Where is this well documented? (Please note that I have grep'ed the source
and manual pages and I do not own "The Design and Implementation of the
4.4BSD Operating System".)

By the way, should I submit my findings to create some manual pages for
the Kernel Manual (manual section 9)?

Thanks,

   Jeremy C. Reed
   http://www.reedmedia.net/