Messages in this thread | | | From | "Adam J. Richter" <> | Date | Thu, 12 Apr 2001 12:15:32 -0700 | Subject | Re: PATCH(?): linux-2.4.4-pre2: fork should run child first |
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>> = 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.
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