From owner-freebsd-questions@FreeBSD.ORG Sat Dec 31 04:34:50 2005 Return-Path: X-Original-To: freebsd-questions@freebsd.org Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 3028E16A41F for ; Sat, 31 Dec 2005 04:34:50 +0000 (GMT) (envelope-from kris@obsecurity.org) Received: from elvis.mu.org (elvis.mu.org [192.203.228.196]) by mx1.FreeBSD.org (Postfix) with ESMTP id DBB6F43D60 for ; Sat, 31 Dec 2005 04:34:49 +0000 (GMT) (envelope-from kris@obsecurity.org) Received: from obsecurity.dyndns.org (elvis.mu.org [192.203.228.196]) by elvis.mu.org (Postfix) with ESMTP id B623C1A3C1D; Fri, 30 Dec 2005 20:34:49 -0800 (PST) Received: by obsecurity.dyndns.org (Postfix, from userid 1000) id 0D5745119E; Fri, 30 Dec 2005 23:34:49 -0500 (EST) Date: Fri, 30 Dec 2005 23:34:48 -0500 From: Kris Kennaway To: Kiffin Gish Message-ID: <20051231043448.GC66216@xor.obsecurity.org> References: <1135855260.1034.5.camel@localhost> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="O3RTKUHj+75w1tg5" Content-Disposition: inline In-Reply-To: <1135855260.1034.5.camel@localhost> User-Agent: Mutt/1.4.2.1i Cc: freebsd-questions@freebsd.org Subject: Re: Using SCHED_ULE vs. SCHED_4BSD ... X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 31 Dec 2005 04:34:50 -0000 --O3RTKUHj+75w1tg5 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Dec 29, 2005 at 12:21:00PM +0100, Kiffin Gish wrote: > I recently upgraded from 5.4 to 6.0 and noticed the introduction of > option SCHED_ULE for supporting multi-processor environments. >=20 > However, I understood that using SCHED_ULE with only one CPU can also > improve performance significantly. >=20 > Is this true, and if so, what are the risks involved dropping good old > SCHED_4BSD for the new-and-improved scheduler? The risks are that you system will perform 10-20% slower under load, and may sometimes panic or spontaneously reboot. In other words: ULE is not production-ready. This may of course change at a later date. Kris --O3RTKUHj+75w1tg5 Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (FreeBSD) iD8DBQFDtgpnWry0BWjoQKURAiEtAJwLdAX3EOSyk85Aiq34llyWH5t43ACfcAxr pprmuu3N0oEZCMZFBmnVuUs= =cMTv -----END PGP SIGNATURE----- --O3RTKUHj+75w1tg5--