From owner-freebsd-scsi Tue May 18 16:39:46 1999 Delivered-To: freebsd-scsi@freebsd.org Received: from allegro.lemis.com (allegro.lemis.com [192.109.197.134]) by hub.freebsd.org (Postfix) with ESMTP id 78AAE14F2D for ; Tue, 18 May 1999 16:39:30 -0700 (PDT) (envelope-from grog@freebie.lemis.com) Received: from freebie.lemis.com (freebie.lemis.com [192.109.197.137]) by allegro.lemis.com (8.9.1/8.9.0) with ESMTP id JAA04018; Wed, 19 May 1999 09:09:23 +0930 (CST) Received: (from grog@localhost) by freebie.lemis.com (8.9.3/8.9.0) id JAA04940; Wed, 19 May 1999 09:09:22 +0930 (CST) Date: Wed, 19 May 1999 09:09:22 +0930 From: Greg Lehey To: Palle Girgensohn Cc: freebsd-scsi@FreeBSD.ORG Subject: Re: Will IDE disks impact SCSI or system performance? Message-ID: <19990519090922.D89091@freebie.lemis.com> References: <37416684.64A54C87@partitur.se> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.95.4i In-Reply-To: <37416684.64A54C87@partitur.se>; from Palle Girgensohn on Tue, May 18, 1999 at 03:09:24PM +0200 WWW-Home-Page: http://www.lemis.com/~grog X-PGP-Fingerprint: 6B 7B C3 8C 61 CD 54 AF 13 24 52 F8 6D A4 95 EF Organization: LEMIS, PO Box 460, Echunga SA 5153, Australia Phone: +61-8-8388-8286 Fax: +61-8-8388-8725 Mobile: +61-41-739-7062 Sender: owner-freebsd-scsi@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Tuesday, 18 May 1999 at 15:09:24 +0200, Palle Girgensohn wrote: > Hi! > > Our main internal server, FreeBSD 3.2b with five large SCSI disks, > running vinum and softupdates etc... It fast, and we're happy. It runs > both filesharing (mainly NFS) and applications. > > Now some guys here are interested in having a large archive with > not-so-important data (read mp3 files...) and suggest a large IDE disk > for almost no money at all. > > My question: will an IDE disk in a now SCSI-only system impact > performance for the rest of the system? Julian sort of answered this, but to be sure: if you run DMA, it shouldn't make any difference. If you run it in PIO mode, you can end up using up to 90% of the processor in interrupt code, which will make it seem like it's grinding to a halt. Greg -- See complete headers for address, home page and phone numbers finger grog@lemis.com for PGP public key To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-scsi" in the body of the message