From owner-freebsd-stable Tue Sep 25 13:49:31 2001 Delivered-To: freebsd-stable@freebsd.org Received: from netau1.alcanet.com.au (ntp.alcanet.com.au [203.62.196.27]) by hub.freebsd.org (Postfix) with ESMTP id 7B22E37B412 for ; Tue, 25 Sep 2001 13:49:26 -0700 (PDT) Received: from mfg1.cim.alcatel.com.au (mfg1.cim.alcatel.com.au [139.188.23.1]) by netau1.alcanet.com.au (8.9.3 (PHNE_22672)/8.9.3) with ESMTP id GAA05467; Wed, 26 Sep 2001 06:49:23 +1000 (EST) Received: from gsmx07.alcatel.com.au by cim.alcatel.com.au (PMDF V5.2-32 #37640) with ESMTP id <01K8S7XKIKEOVMFOB0@cim.alcatel.com.au>; Wed, 26 Sep 2001 06:49:22 +1000 Received: (from jeremyp@localhost) by gsmx07.alcatel.com.au (8.11.1/8.11.1) id f8PKnKd53111; Wed, 26 Sep 2001 06:49:20 +1000 (EST envelope-from jeremyp) Content-return: prohibited Date: Wed, 26 Sep 2001 06:49:20 +1000 From: Peter Jeremy Subject: Re: options HZ=1000 In-reply-to: <200109231401.WAA03886@venus.cyber.mmu.edu.my>; from nuzrin@yahoo.com on Sun, Sep 23, 2001 at 10:15:12PM +0800 To: nuzrin@goose.net.my Cc: freebsd-stable@FreeBSD.ORG Mail-Followup-To: nuzrin@goose.net.my, freebsd-stable@FreeBSD.ORG Message-id: <20010926064920.K75481@gsmx07.alcatel.com.au> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii Content-disposition: inline User-Agent: Mutt/1.2.5i References: <200109231401.WAA03886@venus.cyber.mmu.edu.my> 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 On Sun, Sep 23, 2001 at 10:15:12PM +0800, nuzrin yaapar wrote: >It's regarding the options HZ=1000 in the kernel configuration file. Do >anyone know what impact this setting might have to the overall performance? I have a couple of systems that have HZ=2000 - primarily for accurate dummynet timings. The slowest system is a P-133 and running it at 2000Hz doesn't appear to have caused any problems. The resultant background load is of the order of 1% which isn't a problem for me. Keep in mind that Alpha's run at a fixed HZ=1024 so timing problems will mostly have shown up and been fixed. That said, I have found a problem in the digi(4) driver which has timeouts tied to HZ, rather than wallclock time - similar problems may crop up in other more unusual hardware. Peter To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message