Re: 2.5.47 scheduler problems?

Jim Houston
2002-11-22T05:34:24Z

Hi Mike, Rik, Everyone,

The O(1) schedule just isn't fair. It will run a subset
of the runable processes excluding the rest. See my earlier
emails for the details.

I had been working on a fix for this but got distracted
by Posix timers. I still hope to get back to it.

My patch is here:
http://marc.theaimsgroup.com/?l=linux-kernel&m=103508412423719&w=2

It fixes fairness but breaks nice(2). Rik van Riel has a
patch here which builds on my patch which fixes this:
http://marc.theaimsgroup.com/?l=linux-kernel&m=103651801424031&w=2

I just gave this a spin with. The patches still apply cleanly
to linux-2.5.48 and it seems well behaved:-)

I found this problem with the LTP waitpid06 test. It actually
produced a live-lock. See this mail:
http://marc.theaimsgroup.com/?l=linux-kernel&m=103133744217082&w=2

Jim Houston - Concurrent Computer Corp.