From owner-freebsd-stable Thu Jul 11 13:55:14 2002 Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.FreeBSD.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 5304237B400 for ; Thu, 11 Jul 2002 13:55:11 -0700 (PDT) Received: from herbelot.dyndns.org (d108.dhcp212-198-26.noos.fr [212.198.26.108]) by mx1.FreeBSD.org (Postfix) with ESMTP id 7DF5C43E31 for ; Thu, 11 Jul 2002 13:55:08 -0700 (PDT) (envelope-from thierry@herbelot.com) Received: from herbelot.com (tulipe.herbelot.nom [192.168.2.5]) by herbelot.dyndns.org (8.9.3/8.9.3) with ESMTP id WAA21693; Thu, 11 Jul 2002 22:54:52 +0200 (CEST) (envelope-from thierry@herbelot.com) Message-ID: <3D2DF09C.B553DE07@herbelot.com> Date: Thu, 11 Jul 2002 22:54:52 +0200 From: Thierry Herbelot X-Mailer: Mozilla 4.79 [en] (X11; U; Linux 2.4.2 i386) X-Accept-Language: en MIME-Version: 1.0 To: Matthew Dillon Cc: freebsd-stable@FreeBSD.ORG Subject: Re: tuning(7) request was: Re: Performance boost with kernel options in FBSD 4.6 References: <20020710104730.L10343-100000@klima.physik.uni-mainz.de> <04a601c228dc$c6dbb980$681663cf@icarz.com> <200207111930.g6BJUX5m096974@apollo.backplane.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Matthew Dillon wrote: > > An increased switching rate (increasing HZ) may be useful in the above > situation. Still, I would not recommend increasing Hz above 500 (2ms). > 10000 (100uS) is just plain insane. > from actual experience, any p-III with a clock rate above 500MHz (that is, any recent CPU) can sustain Hz=5000, which I used to run trafific-shaped packet blasters (admittedly a narrow focus ...) with very good results (better than special-purpose test boxes). As is said in the dummynet man page, FreeBSD can be a very good traffic shaper, if the userland scheduling rate is high enough (will it be the same with threads in -current, with KSE ?). many of my machines run with GENERIC and kern.hz=1000 in /boot/loader.conf (I still have to look if NTIMECOUNTER is upped in the same porportion : USTL !) TfH To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message