From owner-freebsd-hackers Wed Sep 22 20:21:14 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from picnic.mat.net (picnic.mat.net [206.246.122.133]) by hub.freebsd.org (Postfix) with ESMTP id AE79B1542F for ; Wed, 22 Sep 1999 20:21:08 -0700 (PDT) (envelope-from chuckr@mat.net) Received: from localhost (localhost [127.0.0.1]) by picnic.mat.net (8.9.3/8.9.3) with ESMTP id XAA64075; Wed, 22 Sep 1999 23:21:02 -0400 (EDT) (envelope-from chuckr@mat.net) Date: Wed, 22 Sep 1999 23:21:02 -0400 (EDT) From: Chuck Robey To: Alfred Perlstein Cc: "Daniel C. Sobral" , Ivan , Matthew Dillon , freebsd-hackers@FreeBSD.ORG Subject: Re: Out of swap handling and X lockups in 3.2R In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Wed, 22 Sep 1999, Alfred Perlstein wrote: > > What kind of resources are there that both cause loss of swap AND are > > freed up by sleeping a process? > > four things i can think of: > > 1) Along with 'SIGDANGER' it allows the system to fix itself. > 2) Allow the operator to determine which program to kill, maybe the > 'hog' is actually something that needs to run to completion and > by shutting down other systems it would survive. > 3) other processes may exit, this would free the memory needed to > continue. > 4) the operator could enable swap on an additional device giving > more backing for things to continue. > > don't forget the clause about killing after putting a threshold of > active processes to sleep. I'm thinking of the HMO administrator walking into an emergency room, seeing a doctor who has asked permission to do an emergency procedure to crack open the chest of someone whose heart has stopped; the HMO administrator asking "have you tried giving him drugs to lower his cholesterol count?" Too little, too late. When the system is paralyzed, any actions that unparalyze it area the only acceptable action set. ---------------------------------------------------------------------------- Chuck Robey | Interests include C programming, Electronics, 213 Lakeside Dr. Apt. T-1 | communications, and signal processing. Greenbelt, MD 20770 | I run picnic.mat.net: FreeBSD-current(i386) and (301) 220-2114 | jaunt.mat.net : FreeBSD-current(Alpha) ---------------------------------------------------------------------------- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message