Date: Sat, 22 Dec 2001 00:06:39 -0800 From: Luigi Rizzo <rizzo@aciri.org> To: Bruce Evans <bde@zeta.org.au> Cc: John Baldwin <jhb@FreeBSD.org>, current@FreeBSD.org, Peter Wemm <peter@wemm.org> Subject: Re: vm_zeropage priority problems. Message-ID: <20011222000639.A22666@iguana.aciri.org> In-Reply-To: <20011222183040.E7393-100000@gamplex.bde.org> References: <20011221095058.A17968@iguana.aciri.org> <20011222183040.E7393-100000@gamplex.bde.org>
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On Sat, Dec 22, 2001 at 06:48:26PM +1100, Bruce Evans wrote: > On Fri, 21 Dec 2001, Luigi Rizzo wrote: ... > > This would help removing the ugly property that priority-based > > have, which is that one process can starve the rest of the system. > > Only broken priority-based schedulers have that property. One of > my incomplete fixes uses weights: which makes it weight based, doesn't it :) > Most of the changes here are to fix style bugs. In the NEW_SCHED case, > the relative weights for each priority are determined by the niceweights[] > table. kg->kg_estcpu is limited only by INT_MAX and priorities are > assigned according to relative values of kg->kg_estcpu (code for this is > not shown). i guess the latter is the hard part... what kind of complexity does it have ? The nice feature of the scheduling code used in dummynet/Wf2Q+ is that it has O(log N) complexity where N is the number of active flows (processes in this case) and the basic scheduling operation is just one or two heap insert/delete, so it's really fast. cheers luigi To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message
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