From owner-freebsd-smp Thu May 2 11: 1:35 2002 Delivered-To: freebsd-smp@freebsd.org Received: from mail.speakeasy.net (mail11.speakeasy.net [216.254.0.211]) by hub.freebsd.org (Postfix) with ESMTP id ADADC37B41A for ; Thu, 2 May 2002 11:01:31 -0700 (PDT) Received: (qmail 22217 invoked from network); 2 May 2002 18:01:30 -0000 Received: from unknown (HELO server.baldwin.cx) ([216.27.160.63]) (envelope-sender ) by mail11.speakeasy.net (qmail-ldap-1.03) with DES-CBC3-SHA encrypted SMTP for ; 2 May 2002 18:01:30 -0000 Received: from laptop.baldwin.cx (gw1.twc.weather.com [216.133.140.1]) by server.baldwin.cx (8.11.6/8.11.6) with ESMTP id g42I1QF08432; Thu, 2 May 2002 14:01:26 -0400 (EDT) (envelope-from jhb@FreeBSD.org) Message-ID: X-Mailer: XFMail 1.5.2 on FreeBSD X-Priority: 3 (Normal) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit MIME-Version: 1.0 In-Reply-To: <3CD1780B.2CC97DDB@mindspring.com> Date: Thu, 02 May 2002 14:00:27 -0400 (EDT) From: John Baldwin To: Terry Lambert Subject: Re: hlt when idle? Cc: Jonathan Mini , Andrew Gallatin , freebsd-smp@FreeBSD.org Sender: owner-freebsd-smp@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org On 02-May-2002 Terry Lambert wrote: > I think the confusion is because it's useful for the clock to > be broadcast for one set of reasons, and it's useful to hit on > only one processor for global handler processing for another > set of reasons. Err, some confusion may be that in current we have two different types of clock interrupt handlers. :) For example, for hardclock, we ahve hardclock() and hardclock_process(). We call hardclock() on only one CPU, and hardclock_process() on all the others. hardclock() does system-wide global changes and then runs the thread-specific hardclock_process(). hardclock_process() does thread-specific things like setting up SIGVTALRM and SIGPROF. Currently hardclock_process() (and even more-so, statclock_process()) use the global sched_lock, thus broadcast doesn't reduce contention unless it is a staggered broadcast. -- John Baldwin <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-smp" in the body of the message