From owner-freebsd-arch Wed Oct 4 19:19:58 2000 Delivered-To: freebsd-arch@freebsd.org Received: from mass.osd.bsdi.com (mass.osd.bsdi.com [204.216.28.234]) by hub.freebsd.org (Postfix) with ESMTP id D7CE637B503 for ; Wed, 4 Oct 2000 19:19:56 -0700 (PDT) Received: from mass.osd.bsdi.com (localhost [127.0.0.1]) by mass.osd.bsdi.com (8.11.0/8.9.3) with ESMTP id e952Leh01021; Wed, 4 Oct 2000 19:21:41 -0700 (PDT) (envelope-from msmith@mass.osd.bsdi.com) Message-Id: <200010050221.e952Leh01021@mass.osd.bsdi.com> X-Mailer: exmh version 2.1.1 10/15/1999 To: Alfred Perlstein Cc: arch@FreeBSD.ORG Subject: Re: Mutexes and semaphores In-reply-to: Your message of "Wed, 04 Oct 2000 18:46:00 PDT." <20001004184559.Q27736@fw.wintelcom.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Wed, 04 Oct 2000 19:21:40 -0700 From: Mike Smith Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > the idea is to reduce inter-cpu communication, lock-less systems are a > terrific idea but hard to get right, we have two choices: > > 1) do it right and _not_ cause extra lock/cpu/bus contention > 2) do it right and cause extra lock/cpu/bus contention > > It's my opinion that something simple like getpid shouldn't cause a > locked bus cycle if at all possible. Under the circumstances, there are so many other things that we should be worrying about that the trivial performance win here is entirely offset by the confusion and irritation that it may cause later if we violate the assumptions this code makes. -- ... every activity meets with opposition, everyone who acts has his rivals and unfortunately opponents also. But not because people want to be opponents, rather because the tasks and relationships force people to take different points of view. [Dr. Fritz Todt] V I C T O R Y N O T V E N G E A N C E To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message