From owner-freebsd-hackers Wed Apr 11 16:19: 3 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from fw.wintelcom.net (ns1.wintelcom.net [209.1.153.20]) by hub.freebsd.org (Postfix) with ESMTP id 794E337B422 for ; Wed, 11 Apr 2001 16:18:59 -0700 (PDT) (envelope-from bright@fw.wintelcom.net) Received: (from bright@localhost) by fw.wintelcom.net (8.10.0/8.10.0) id f3BNIwT16523; Wed, 11 Apr 2001 16:18:58 -0700 (PDT) Date: Wed, 11 Apr 2001 16:18:58 -0700 From: Alfred Perlstein To: Doug White Cc: Dan Phoenix , freebsd-hackers@FreeBSD.ORG Subject: Re: lockf in apache Message-ID: <20010411161858.T15938@fw.wintelcom.net> References: <20010410131254.V15938@fw.wintelcom.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: ; from dwhite@resnet.uoregon.edu on Wed, Apr 11, 2001 at 04:07:25PM -0700 X-all-your-base: are belong to us. Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG * Doug White [010411 16:07] wrote: > On Tue, 10 Apr 2001, Alfred Perlstein wrote: > > > Basically, when apache is listening on multiple IPs/ports it needs > > to select() on several filedescriptors. The problem (under FreeBSD > > at least) is that whenever you have some process select()'ing on > > a descriptor and another process wants to do the same you get a > > "select collision", a collision requires that all processes waiting > > on the same select channel wake up then reassert thier desire to > > select. So... if you have 500 apache processes select()'ing and > > one wakes up to service a request, finished serving, then goes to > > select again, all the rest (499) have to wake up and reaffirm thier > > desire to select(). > > We haven't applied wakeup_one() to select() yet? (I think I've argued > about this before.) > > Someone get cracking! :) I'm not sure it's possible without redesigning the way select works. -- -Alfred Perlstein - [bright@wintelcom.net|alfred@freebsd.org] Daemon News Magazine in your snail-mail! http://magazine.daemonnews.org/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message