Re: I wrote a kernel tool for monitoring / web page

Lee Revell
2005-02-19T02:52:31Z

On Sat, 2005-02-19 at 02:33 +0100, sylvanino b wrote:
> Sorry, it's meant to run on linux.
> Actually, patch provided is for linux 2.6.9 + kdb 4.4
>

Cool program. It has an annoying bug where every time you go to "Open
Log File", it starts you in your home directory again. Otherwise it's a
nice utility.

I actually have a problem that this might help with. The issue is that
the scheduler seems to treat Evolution as a CPU bound rather than an
event driven, I/O bound process. The most obvious symptom is that a
real CPU bound activity like a kernel compile will cause navigating the
message list in Evolution to slow to a crawl. Evolution is perfectly
usable when no other CPU hogs are running, or when the CPU hogs are
niced, so it's definitely a scheduler issue.

My understanding of Unix schedulers is that the basic idea is to
penalize CPU bound and reward I/O bound processes by giving the former
lower dynamic priority with longer timeslice and the latter high
priority with shorter timeslice. I suspect the scheduler does not
handle interactive, event driven apps that also consume a lot of CPU due
to bloat very well. These would seem to need high priority and long
timeslices, which would require the scheduler to distinguish a process
like a kernel compile that will continually exhaust its timeslice no
matter how long, and a process like evolution that if given a long
enough timeslice will finish rendering the message and go back to sleep.

Anyway, that's my hypothesis, I'll let you know what I find out.

Lee