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SubjectRe: PATCH(?): linux-2.4.4-pre2: fork should run child first
>> = Adam J. Richter <adam@yggdrasil.com>
> = Horst von Brand <vonbrand@inf.utfsm.cl>

>> I suppose that running the child first also has a minor
>> advantage for clone() in that it should make programs that spawn lots
>> of threads to do little bits of work behave better on machines with a
>> small number of processors, since the threads that do so little work that
>> they accomplish they finish within their time slice will not pile up
>> before they have a chance to run. So, rather than give the parent's CPU
>> priority to the child only if CLONE_VFORK is not set, I have decided to
>> do a bit of machete surgery and have the child always inherit all of the
>> parent's CPU priority all of the time. It simplifies the code and
>> probably saves a few clock cycles (and before you say that this will
>> cost a context switch, consider that the child will almost always run
>> at least one time slice anyhow).

>And opens the system up to DoS attacks: You can't have a process fork(2)
>at will and so increase its (aggregate) CPU priority.

My change does not increase the aggregate priority of
parent+child. Perhaps I misunderstand your comment.

Adam J. Richter __ ______________ 4880 Stevens Creek Blvd, Suite 104
adam@yggdrasil.com \ / San Jose, California 95129-1034
+1 408 261-6630 | g g d r a s i l United States of America
fax +1 408 261-6631 "Free Software For The Rest Of Us."
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