From: Johnny Billquist  <bqt@minsk.docs.uu.se>
Date: Sun, 14 Sep 97 1:49:54 +0300 (MET DST)
Reply-To: bqt@minsk.docs.uu.se
To: allisonp@world.std.com (Allison J Parent)
Cc: pups@minnie.cs.adfa.oz.au
Subject: Re: UNIX for PDP-11: moving on to media
In-Reply-To: Your message of Sat, 13 Sep 1997 17:58:38 -0400
Message-Id: <CMM.0.90.0.874194594.bqt@Minsk.DoCS.UU.SE>
Sender: owner-pups@minnie.cs.adfa.oz.au
Precedence: bulk

>
><Most RL02 are pretty good. Usually they don't have any bad spots in my
><experience.
>
>They were low in defects<frequently none> but there was remaping so platters 
>with bad blocks were invisible to the system mangler/user.  I just tossed a 
>pack that had developed more bad blocks then could be managed.

No exacly invisible... The operating system had to be aware of the bad spots,
and invent some scheme or other to hide the spots from the user.

OS/8's solution is rather hairy. I know, since I didn't have a "formatter"
program, so I needed to write one, given the source of the device driver...

Bad spots on MSCP disks on the other hand are totally invisible.

	Johnny

Johnny Billquist                  || "I'm on a bus
CS student at Uppsala University  ||  on a psychedelic trip
email: bqt@minsk.docs.uu.se       ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol