Re: [REPORT] cfs-v4 vs sd-0.44

[Linus Torvalds]

On Sat, 21 Apr 2007, Willy Tarreau wrote:
> 
> If you remember, with 50/50, I noticed some difficulties to fork many
> processes. I think that during a fork(), the parent has a higher probability
> of forking other processes than the child. So at least, we should use
> something like 67/33 or 75/25 for parent/child.

It would be even better to simply have the rule:
 - child gets almost no points at startup
 - but when a parent does a "waitpid()" call and blocks, it will spread 
   out its points to the childred (the "vfork()" blocking is another case 
   that is really the same).

This is a very special kind of "priority inversion" logic: you give higher 
priority to the things you wait for. Not because of holding any locks, but 
simply because a blockign waitpid really is a damn big hint that "ok, the 
child now works for the parent".

		Linus
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