Path: utzoo!utgpu!watmath!att!cuuxb!fmcgee From: fmcgee@cuuxb.ATT.COM (~XT6510300~Frank McGee~C23~L25~6326~) Newsgroups: comp.unix.i386 Subject: Re: How many users _really_ ? Summary: might want to take a closer look Keywords: disk i/o performance Message-ID: <4134@cuuxb.ATT.COM> Date: 29 Aug 89 18:55:43 GMT Expires: 13 Oct 89 23:00:00 GMT References: <1045@aber-cs.UUCP> <32824@apple.Apple.COM> Reply-To: fmcgee@cuuxb.UUCP (Frank W. McGee) Followup-To: comp.unix.i386 Distribution: na Organization: AT&T Computer Systems, Lisle, IL Lines: 27 In article pcg@thor.cs.aber.ac.uk (Piercarlo Grandi) writes: >The same is true, with adjustments, on a 386. A 386 with one 300 meg >drive is MUCH slower than one with two 150 meg ones, preferably on a >multithreaded controller (e.g. AHA154x) or on two single threaded >controllers, especially if the disc partitioning is done ok. There are some cases where a single large drive will perform better than two smaller ones. A lot of controllers out there in PC-AT land are not as smart as many of us would like. For instance, the Western Digital 1007-WAH controller has a 16K track buffer on it. If you have one disk, it helps with performance. If you have two disks, performance gets worse because it can't use the track buffer as much as with a single disk (it has to be flushed before it can read/write to the other disk). With this particular controller, one 300 MB is better than two 150's. If you have multiple controllers or SCSI your statement would be very true though. Frank McGee, AT&T Tier 3 Indirect Channel Sales Support attmail!fmcgee -- Frank McGee, AT&T Tier 3 Indirect Channel Sales Support attmail!fmcgee