From owner-freebsd-arch Tue Nov 2 13:16:19 1999 Delivered-To: freebsd-arch@freebsd.org Received: from ns1.yes.no (ns1.yes.no [195.204.136.10]) by hub.freebsd.org (Postfix) with ESMTP id BCF8A1501B for ; Tue, 2 Nov 1999 13:16:08 -0800 (PST) (envelope-from eivind@bitbox.follo.net) Received: from bitbox.follo.net (bitbox.follo.net [195.204.143.218]) by ns1.yes.no (8.9.3/8.9.3) with ESMTP id WAA27217 for ; Tue, 2 Nov 1999 22:16:07 +0100 (CET) Received: (from eivind@localhost) by bitbox.follo.net (8.8.8/8.8.6) id WAA82393 for freebsd-arch@freebsd.org; Tue, 2 Nov 1999 22:16:06 +0100 (MET) Received: by hub.freebsd.org (Postfix, from userid 758) id B41891501B; Tue, 2 Nov 1999 13:14:01 -0800 (PST) Received: from localhost (localhost [127.0.0.1]) by hub.freebsd.org (Postfix) with ESMTP id A84A81CD75C; Tue, 2 Nov 1999 13:14:01 -0800 (PST) (envelope-from kris@hub.freebsd.org) Date: Tue, 2 Nov 1999 13:14:01 -0800 (PST) From: Kris Kennaway To: "Daniel M. Eischen" Cc: Julian Elischer , freebsd-arch@freebsd.org Subject: Re: Threads models and FreeBSD. (Next Step) In-Reply-To: <381ED720.5A24A02B@vigrid.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Tue, 2 Nov 1999, Daniel M. Eischen wrote: > Julian Elischer wrote: > > > > Here is an updated version of the rather simplistic requirements for a > > threads model for freeBSD. > [...] > > > > 1/ Multiple independent 'threads of control' within a single process > > at user level. The most basic quality of threads. > > > > 2/ Ability to simultaneously schedule M threads over N Processors, > > and have min(M,N) threads simultaneously executing. > > Shouldn't this be M threads over N [lightweight] Processes? A better wording might be "N virtual processors", or (Terry's terminology) "Kernel Schedulable Entities (KSEs)" to abstract what is used as backing in the kernel, i.e. what actually gets run by the kernel on the physical processors. > How about [from the "scheduler activations" paper] Flexibility? I assume by this you mean "the ability to replace the user-level code with another model". In theory, that's a good goal, and it's one we shouldn't work against, but in practise there's only likely to be one (supported) FreeBSD user-threading library which interfaces to the kernel support. ---- Cthulhu for President! For when you're tired of choosing the _lesser_ of two evils.. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message