Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!ames!pasteur!ucbvax!hplabs!hp-sdd!artecon!sceard!mrm From: mrm@sceard.UUCP (M.R.Murphy) Newsgroups: comp.unix.microport Subject: Re: Hard Disks for AT Keywords: disagree Message-ID: <831@sceard.UUCP> Date: 23 Sep 88 01:31:31 GMT References: <409@ucrmath.UUCP> <1181@umbc3.UMD.EDU> Reply-To: mrm@sceard.UUCP (0040-M.R.Murphy) Organization: Sceard Systems, Inc., San Marcos, CA 92069 Lines: 44 In article <1181@umbc3.UMD.EDU> brian@umbc3.UMD.EDU (Brian Cuthie) writes: )In article <409@ucrmath.UUCP> jantypas@Soft21.Riverside.CA.US (John Antypas) writes: )>Hello out there! )> )>Can someone out there help me? I am running Microport Unix Sys V/AT )>[deleted] )>What types of drives can an AT use? (Standard MFM Western Digital controller) )>[deleted] )>Many thanks. )> )>John Antypas -- Soft21 --21st Century Software: ) )Well, stay away from the Seagate drives. They are pure crap. They quote )their access times a little funny. Like claiming that their average seek )time is 28 ms on the 4096 when the track to track time is 8 or 9 ms ! Any )good drive will have a voice coil actuator that can deliver a track to track )time below 6 ms. ) )There are several manufacturers who make good, fast, drives. These include )MAXTOR, CDC, PRIAM and some more that escape my memory now. It is very )important not to underestimate the amount of time spent waiting for a slow )disk drive. There is no point in running UNIX on a fast processor just to )slow it down with a piggy drive. ) )Hope this helps... ) )-brian We use ST4096 drives with WD controllers on uPORT SVAT and don't find the systems "piggy". Also ST251-1 drives. Prices are reasonable. Unix(tm) file system caching helps. "... In our own system, for example, we have user files on an RP, the root on an RF fixed-head disk, and swap on an RK. This is best for us since the RK has a faster transfer rate than the rather slow RF, and in swapping the transfer rate rather than access time is the dominant influence on throughput." SETTING UP UNIX -- Sixth Edition Transfer rate is still important. The effects of small memories coupled with slow disks are easy to observe, not so easy to measure. It really seems to help when SVAT has 1100K of buffers rather than 100K of buffers. It also seems to help when the disk is 28ms rather than 70ms :-) -- Mike Mike Murphy Sceard Systems, Inc. 544 South Pacific St. San Marcos, CA 92069 ARPA: sceard!mrm@nosc.MIL BITNET: MURPHY@UCLACH UUCP: ucsd!sceard!mrm INTERNET: mrm%sceard.UUCP@ucsd.ucsd.edu