From owner-freebsd-arch Thu Nov 9 15:12:42 2000 Delivered-To: freebsd-arch@freebsd.org Received: from mail-relay.eunet.no (mail-relay.eunet.no [193.71.71.242]) by hub.freebsd.org (Postfix) with ESMTP id D20CE37B4CF; Thu, 9 Nov 2000 15:12:38 -0800 (PST) Received: from login-1.eunet.no (login-1.eunet.no [193.75.110.2]) by mail-relay.eunet.no (8.9.3/8.9.3/GN) with ESMTP id AAA61220; Fri, 10 Nov 2000 00:12:36 +0100 (CET) (envelope-from mbendiks@eunet.no) Received: from localhost (mbendiks@localhost) by login-1.eunet.no (8.9.3/8.8.8) with ESMTP id AAA25171; Fri, 10 Nov 2000 00:12:36 +0100 (CET) (envelope-from mbendiks@eunet.no) X-Authentication-Warning: login-1.eunet.no: mbendiks owned process doing -bs Date: Fri, 10 Nov 2000 00:12:36 +0100 (CET) From: Marius Bendiksen To: Poul-Henning Kamp Cc: arch@freebsd.org Subject: Re: Green/Yellow/Red state for the VM system. In-Reply-To: <28041.973635706@critter> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Sounds good to me, but I have a small alteration to suggest. You might want to introduce the color ORANGE, instead of yellow, and have yellow and green be per-subsystem states, and orange and red be global, so as to be able to adapt more gradually to the impending highwatermark. Also, I'd suggest going through with the idea of posting signals to user processes before hitting a real high water mark, preferrably also color coded, as opposed to SIGDANGER, which I don't see as much use in. The use of color, however, when extended into userland, allows software doing clustering and such to signal that the other hosts in the cluster should cover for it, and that it does not want any more load. The use of a black or green signal (depending on granularity) to say "act normal" prevents severe DoS attacks, I think. --- Marius Bendiksen To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message