From owner-freebsd-hackers@FreeBSD.ORG Sun Mar 6 08:40:50 2005 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id DB00016A4CE for ; Sun, 6 Mar 2005 08:40:50 +0000 (GMT) Received: from wattres.watt.com (wattres.watt.com [66.93.133.130]) by mx1.FreeBSD.org (Postfix) with ESMTP id 76A1F43D53 for ; Sun, 6 Mar 2005 08:40:50 +0000 (GMT) (envelope-from steve@Watt.COM) Received: from wattres.watt.com (localhost.watt.com [127.0.0.1]) by wattres.watt.com (8.13.1/8.13.1) with ESMTP id j268eiSa004556 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sun, 6 Mar 2005 00:40:44 -0800 (PST) (envelope-from steve@wattres.watt.com) Received: (from steve@localhost) by wattres.watt.com (8.13.1/8.13.1/Submit) id j268eiPT004555; Sun, 6 Mar 2005 00:40:44 -0800 (PST) (envelope-from steve) Message-Id: <200503060840.j268eiPT004555@wattres.watt.com> X-Newsgroups: local.freebsd-hackers In-Reply-To: <20050304032003.89305.qmail@web52702.mail.yahoo.com> Organization: Watt Consultants From: steve@Watt.COM (Steve Watt) Date: Sun, 6 Mar 2005 00:40:44 -0800 X-Mailer: Mail User's Shell (7.2.6 beta(5) 10/07/98) To: kamalp@acm.org X-Archived: 1110098444.794883152@wattres.Watt.COM X-Virus-Scanned: ClamAV 0.83/748/Fri Mar 4 14:19:11 2005 on wattres.Watt.COM X-Virus-Status: Clean cc: hackers@freebsd.org Subject: Re: sched_4BSD X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 06 Mar 2005 08:40:51 -0000 [ Attempted to clean up citations, apologies if I mis-attribute something ] In article <20050304032003.89305.qmail@web52702.mail.yahoo.com>, Kamal R. Prasad wrote: Kamal>--- Julian Elischer wrote: Julian> Kamal R. Prasad wrote: Kamal>>--- Julian Elischer wrote: Julian>>Kamal R. Prasad wrote: Kamal>>>Maybe the freebsd implementation should implement Kamal>>>NPTL in entirety. Julian>>NPTL? Julian>>New Pthreads Library from Library? No, Native POSIX Threads Library for Linux. It's a Linux implementation of kernel-level threads that was spearheded by Ulrich Drepper. It fixes most (all?) of the ugly signal problems that LinuxThreads had. Kamal>>Yes. Julian>>isn't that GPL'd? Yes. Kamal>No -it is a standard. The linux implementation of nptl Kamal>is gpl'ed. No, POSIX 1003.1 is the standard, the thread portion was known for some time as 1003.1c, but was combined in with the base. NPTL is a particular (less brain damaged than LinuxThreads) implementation of the POSIX thread standard. Likewise, scheduler activations are a decent implementation of threads. I'll refrain from commenting further about libc_r. Julian> so how does that differ from what we have ... a Julian> native pthreads library? Kamal>I just said if it was conformant with NPTL, thread and Kamal>process scheduling would co-exist. Uh, as far as I understand, in NPTL, each thread gets a scheduler slot, and it is my understanding that there is nothing to protect against the issue that Julian is asking about (1000 threads of a single process *do* get 1000 times the time slices). Whether that is a bug or a feature depends very heavily on the system load. -- Steve Watt KD6GGD PP-ASEL-IA ICBM: 121W 56' 57.8" / 37N 20' 14.9" Internet: steve @ Watt.COM Whois: SW32 Free time? There's no such thing. It just comes in varying prices...