From owner-freebsd-current Tue Aug 25 13:41:17 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id NAA00982 for freebsd-current-outgoing; Tue, 25 Aug 1998 13:41:17 -0700 (PDT) (envelope-from owner-freebsd-current@FreeBSD.ORG) Received: from dingo.cdrom.com (ppp-d2.dialup.hilink.com.au [203.2.144.12]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id NAA00964; Tue, 25 Aug 1998 13:40:55 -0700 (PDT) (envelope-from mike@dingo.cdrom.com) Received: from dingo.cdrom.com (localhost [127.0.0.1]) by dingo.cdrom.com (8.9.1/8.8.8) with ESMTP id NAA02533; Tue, 25 Aug 1998 13:38:19 GMT (envelope-from mike@dingo.cdrom.com) Message-Id: <199808251338.NAA02533@dingo.cdrom.com> X-Mailer: exmh version 2.0.2 2/24/98 To: Michael Hancock cc: Gary Palmer , Chuck Robey , freebsd-current@FreeBSD.ORG Subject: Re: Threads across processors In-reply-to: Your message of "Wed, 26 Aug 1998 00:08:50 +0900." Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Tue, 25 Aug 1998 13:38:18 +0000 From: Mike Smith Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > On Tue, 25 Aug 1998, Gary Palmer wrote: > > > Heck, SMI wrote `doors' for the very reason that IPC *blows* in all cases, and > > that to pull off the speedups with NSCD that they wanted, they had to get the > > IPC overhead reduced a lot. I think I even have slides somewhere comparing > > pipes, SYSV SHM, etc times for message passing in terms of transit time. > > Our pipes are very fast. SYSV SHM's blunder is that it uses full blown > system calls for synchronization. Yes. Anyone that thinks in terms of a context switch per transaction between coprocesses is not designing properly. Using a shared mmap() region and datastructures that don't require locking is another cost-effective technique. -- \\ Sometimes you're ahead, \\ Mike Smith \\ sometimes you're behind. \\ mike@smith.net.au \\ The race is long, and in the \\ msmith@freebsd.org \\ end it's only with yourself. \\ msmith@cdrom.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message