From owner-freebsd-chat Wed Feb 5 10:29:53 2003 Delivered-To: freebsd-chat@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 88E6137B401 for ; Wed, 5 Feb 2003 10:29:52 -0800 (PST) Received: from haldjas.folklore.ee (Haldjas.folklore.ee [193.40.6.121]) by mx1.FreeBSD.org (Postfix) with ESMTP id 8ABFA43F43 for ; Wed, 5 Feb 2003 10:29:51 -0800 (PST) (envelope-from narvi@haldjas.folklore.ee) Received: from haldjas.folklore.ee (localhost [127.0.0.1]) by haldjas.folklore.ee (8.12.3/8.11.3) with ESMTP id h15ITnOs009887; Wed, 5 Feb 2003 20:29:50 +0200 (EET) (envelope-from narvi@haldjas.folklore.ee) Received: from localhost (narvi@localhost) by haldjas.folklore.ee (8.12.3/8.12.3/Submit) with ESMTP id h15ITmWM009884; Wed, 5 Feb 2003 20:29:49 +0200 (EET) Date: Wed, 5 Feb 2003 20:29:48 +0200 (EET) From: Narvi To: Dag-Erling Smorgrav Cc: freebsd-chat@FreeBSD.ORG Subject: Re: Project status In-Reply-To: Message-ID: <20030205201148.F43637-100000@haldjas.folklore.ee> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-chat@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org On Tue, 4 Feb 2003, Dag-Erling Smorgrav wrote: > - KSE ("kernel scheduled entities") is a threading architecture, both > for in-kernel threads and for mapping userland threads onto kernel > threads (which allows splitting one application across multiple > CPUs; our current thread library doesn't). I don't know of any > substantial opposition against KSE. There are some concerns that > the M-on-N model is not really better than the 1-on-1 model, > especially now that Solaris has switched to the latter, and that > KSE is over-engineered and possibly out of the reach of a team of > (relatively) amateur volunteers. Otherwise, complaints regarding > KSE are mostly about how much time it's taking to implement, and > concerns that the KSE developers aren't subjecting their code to > sufficient testing before committing it. Note that I'm neither > confirming or refuting any of these claims, just reporting what > other people are saying about KSE. > the N:M and especially the 1:1 models are also slightly simplified pictures. I think this is also a cyclical development problem - at some point using 1:1 threads is insufficent and/or doesn't give acceptable perfomace so the move to N:M happens. At some point later, kernel based threads are again sufficently perfomant that N:M becomes unnecessary complexity. Linux/*BSD are just a cycle behind Solaris in this area. Ultimately the cycles don't matter, what matters is the perfomance and capabilities you deliver. > DES > -- > Dag-Erling Smorgrav - des@ofug.org > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-chat" in the body of the message