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    DateSat, 21 Apr 2007 09:34:07 -0700 (PDT)
    FromLinus Torvalds <>
    SubjectRe: [REPORT] cfs-v4 vs sd-0.44
    
    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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