On Aug 14, 2023, at 1:48 PM, Milo Velimirović
<milovelimirovic(a)gmail.com> wrote:
On Aug 14, 2023, at 11:52 AM, Paul Koning via
cctalk <cctalk(a)classiccmp.org> wrote:
On Aug 14, 2023, at 12:42 PM, Chuck Guzis
<cclist(a)sydex.com> wrote:
On 8/14/23 06:07, Paul Koning wrote:
>
https://ia800809.us.archive.org/30/items/TNM_Control_Data_807-808_Disk_File…
That drive was the fastest transferring disk, by a large margin, for quite a while.
Didn't Cray use multiple bits in parallel disk drives in the Cray-1?
I recall that the first time I heard the term "RAID", it was from one
of
my friends from Cray. I thought it was pretty innovative.
It's been a while, but I think that RAID originated in academia, though Cray may well
have been one of the earlier commercial users.
This is probably one of the earlier papers on RAID that came from Academia from the group
that invented it.
https://www2.eecs.berkeley.edu/Pubs/TechRpts/1987/5853.htmlA Case for Redundant Arrays of
Inexpensive Disks (RAID) | EECS at UC Berkeley
eecs.berkeley.edu
<touch-icon.png>
"Increasing performance of CPUs and memories will be squandered if not matched by a
similar performance increase in I/O. While the capacity of Single Large Expensive Disk
(SLED) has grown rapidly, the performance improvement of SLED has been modest. Redundant
Arrays of Inexpensive Disks (RAID), based on the magnetic disk technology developed for
personal computers, offers an attractive alternative to SLED, promising improvements of an
order of magnitude in performance, reliability, power consumption, and scalability.
This paper introduces five levels of RAIDs, giving their relative cost/performance, and
compares RAIDs to an IBM 3380 and a Fugitsu[sic] Super Eagle.
That fits what I was thinking about.
What I was
referring to wasn't RAID but rather single drives with parallel (multiple tracks
concurrently) transfer, just like the 807/808. Does that ring any bells?
This sounds like it’s similar to, but not the same as fixed-head disk, or head-per-track
disks. DEC had several models of relatively low capacity in the 1970s positioned as
swapping devices with capacities from 128kB to 2048kB.
But all those, drums as well as fixed head disks, are serial devices. Not that they need
to be; given head per track it's clearly straightforward to do parallel recording, but
certainly the DEC devices do not do so.
Or were you thinking of something more recent, like
this:
https://techmonitor.ai/technology/designs_disk_arrays_with_ncr_parallel_dis…
DISK ARRAYS WITH NCR, PARALLEL DISKS WITH CRAY RESEARCH
techmonitor.ai
That seems to be the one, at least at the abstract level it matches what (very
little) I remembered. Is this a Cray 1 era article?
paul