Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!lll-lcc!ames!ucbcad!ucbvax!decvax!tektronix!tekcrl!tekgvs!toma From: toma@tekgvs.UUCP (Thomas Almy) Newsgroups: comp.sys.ibm.pc,comp.periphs Subject: Re: Lot's of questions Message-ID: <1987@tekgvs.UUCP> Date: Mon, 5-Jan-87 11:14:09 EST Article-I.D.: tekgvs.1987 Posted: Mon Jan 5 11:14:09 1987 Date-Received: Tue, 6-Jan-87 18:58:39 EST References: <9073FIB@PSUVM> <2750@osu-eddie.UUCP> <434@catnip.UUCP> <551@brl-sem.ARPA> <1029@cad.cs.cmu.edu> Reply-To: toma@tekgvs.UUCP (Thomas Almy) Organization: Tektronix, Inc., Beaverton, OR. Lines: 21 Xref: mnetor comp.sys.ibm.pc:802 comp.periphs:101 Well I had to comment on Bernoulli Box performance matter. I "Beta tested" both their original 8" 10 Meg drive and 5" 5 Meg drive, and found that the drive performance depended greatly on the driver code. I wrote my own drivers for the drives, and the system was a Compupro S-100 based with a 8 Mhz 8086, running CP/M-86. The drives have the rotational latency and seek times of slower hard disks, but the (voice coil) head positioners are not energized between commands. This means that a seek must be performed before each read or write. The servo positioners seek time is not really that much better for seeking the current track than it is for seeking across the disk! Drivers that read and write a single sector at a time run REAL slow, hardly faster than a floppy, because of those seeks. When full track buffering is performed (I buffered several tracks) then the performace is that of a slow hard disk with full track buffering! Which, by the way, is much faster than a fast hard disk without track buffering. Tom Almy Tektronix, Inc.