From: paul.winalski@gmail.com (Paul Winalski)
Subject: [TUHS] Disk data layout (was: /dev/drum)
Date: Wed, 25 Apr 2018 17:17:49 -0400 [thread overview]
Message-ID: <CABH=_VRWFy7wESGkTNLnZTWmyc3XR0zDKG4hS1TzZfqT6j8YPg@mail.gmail.com> (raw)
In-Reply-To: <20180425013134.GM31055@eureka.lemis.com>
On 4/24/18, Greg 'groggy' Lehey <grog at lemis.com> wrote:
>
> "LBA" is newer than the time we're talking of. In those days, disk
> data was addressed physically, by cylinder, head and sector, terms
> that only died out round the turn of the century.
IBM DASD--Direct Access Storage Device, a term that encompassed drums,
disks and the data cell drive--addressed data on the media physically
by bin, cylinder, head, and record, as a hexadecimal number BBCCHHR.
Bin number was zero except on the IBM 2321 data cell drive. CKD
drives supported a variable number of records on each track, hence the
term "record" rather than "sector".
Logical block addressing (LBA) for sector-oriented disks allowed the
OS (or later, the disk controller) to hide bad block replacement from
programs.
VAX/VMS used a protected system file ([sysexe]badblock.sys) to keep
track of the bad blocks on each disk volume. DEC once got a customer
bug report complaining that if a privileged user gave the command
"TYPE SYS$SYSTEM:BADBLOCK.SYS", the console logged bad block errors.
How does/did Unix handle bad block replacement?
-Paul W.
next prev parent reply other threads:[~2018-04-25 21:17 UTC|newest]
Thread overview: 59+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-04-20 15:02 [TUHS] /dev/drum Tim Bradshaw
2018-04-20 15:58 ` Clem Cole
2018-04-20 16:00 ` David Collantes
2018-04-20 16:12 ` Dan Cross
2018-04-20 16:21 ` Clem Cole
2018-04-20 16:33 ` Warner Losh
2018-04-20 19:17 ` Ron Natalie
2018-04-20 20:23 ` Clem Cole
2018-04-20 22:10 ` Dave Horsfall
2018-04-22 17:01 ` Lars Brinkhoff
2018-04-22 17:37 ` Clem Cole
2018-04-22 19:14 ` Bakul Shah
2018-04-22 20:58 ` Mutiny
2018-04-22 22:37 ` Clem cole
2018-04-22 21:51 ` Dave Horsfall
2018-04-25 1:27 ` Dan Stromberg
2018-04-25 12:18 ` Ronald Natalie
2018-04-25 13:39 ` Tim Bradshaw
2018-04-25 14:02 ` arnold
2018-04-25 14:59 ` tfb
2018-04-25 14:33 ` Ian Zimmerman
2018-04-25 14:46 ` Larry McVoy
2018-04-25 15:03 ` ron minnich
2018-04-25 20:29 ` Paul Winalski
2018-04-25 20:45 ` Larry McVoy
2018-04-25 21:14 ` Lawrence Stewart
2018-04-25 21:30 ` ron minnich
2018-04-25 23:01 ` Bakul Shah
2018-04-23 16:42 ` Tim Bradshaw
2018-04-23 17:30 ` Ron Natalie
2018-04-23 17:51 ` Clem Cole
2018-04-23 18:30 ` Ron Natalie
2018-04-25 14:02 ` Tom Ivar Helbekkmo
2018-04-25 14:38 ` Clem Cole
2018-04-23 20:47 ` Grant Taylor
2018-04-23 21:06 ` Clem Cole
2018-04-23 21:14 ` Dan Mick
2018-04-23 21:27 ` Clem Cole
2018-04-24 3:28 ` [TUHS] 3330s, 3340s, Winchesters... (was: /dev/drum) Greg 'groggy' Lehey
2018-04-24 11:43 ` Paul Winalski
2018-04-24 13:13 ` Clem Cole
2018-04-25 0:52 ` Greg 'groggy' Lehey
2018-04-25 20:54 ` Paul Winalski
2018-04-23 22:07 ` [TUHS] /dev/drum Tim Bradshaw
2018-04-23 22:15 ` Warner Losh
2018-04-23 23:30 ` Grant Taylor
2018-04-24 9:37 ` Michael Kjörling
2018-04-24 9:57 ` Dave Horsfall
2018-04-24 13:01 ` Nemo
2018-04-24 13:03 ` Arthur Krewat
2018-04-25 1:31 ` [TUHS] Disk data layout (was: /dev/drum) Greg 'groggy' Lehey
2018-04-25 6:43 ` Hellwig Geisse
2018-04-25 21:17 ` Paul Winalski [this message]
2018-04-25 21:55 ` Bakul Shah
2018-04-27 15:47 ` Dave Horsfall
2018-04-27 18:16 ` Paul Winalski
2018-04-27 18:37 ` Clem Cole
2018-04-23 23:45 ` [TUHS] /dev/drum Arthur Krewat
2018-04-24 8:05 ` tfb
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