Path: utzoo!mnetor!uunet!tektronix!sequent!mntgfx!dclemans
From: dclemans@mntgfx.mentor.com (Dave Clemans)
Newsgroups: comp.sys.atari.st
Subject: Re: SH204 hard disk
Message-ID: <1988Jan22.085124.4158@mntgfx.mentor.com>
Date: 22 Jan 88 16:51:20 GMT
References: <2697@dadla.TEK.COM>
Organization: Mentor Graphics Corporation, Beaverton Oregon
Lines: 27

Supedit from Supra is a maintainence/diagnostic utility that lets you
examine/patch partition tables, boot sectors, etc. of ST hard disks.

In general, speed problems on ST disks (either floppies or hard disks)
are caused almost solely by the fact that the current GEMDOS uses an
INCREDIBLY! slow routine to search the file allocation table.  (In fact,
from the testing I've done almost the only way Digital Research could
have written a slower search routine would have been to put in wait
loops).  The FAT is hit more heavily on writes which is why writes
are slower than reads.

Hopefully the upcoming GEMDOS rewrite from Atari (when/if it hits
the streets) should address the disk speed problem.  (and it had better
also fix the GEMDOS memory management problems.  I'm really tired
of the "40 folder" and the "20 Malloc" bugs...)

As another example I have a directory cloner that sits on top of a
complete re-implementation of the GEMDOS filesystem (the only part
of the ST roms I use are the getbpb and rwabs calls).  While I don't
remember exact timings, it runs a number of times faster than any
copy routine built on top of GEMDOS and it doesn't slow down dramatically
when writing to very full large disk partitions.

As to "chkdsk" functionality; both disk reorganizer packages I know
about include a "chkdsk".

dgc