Re: The Seymour Cray Era of Supercomputers

On Wed, 21 May 2025 16:09:13 -0000 (UTC)
John Levine <johnl@taugh.com> wrote:

According to Michael S  <already5chosen@yahoo.com>:

According to Michael S  <already5chosen@yahoo.com>: 

At time of introduction CDC 6600 was undoubtedly much faster both
than older [more expensive] IBM 7030 and than contemporary
[significantly less expensive] S/360 Model 50. But it was not
"orders of magnitude faster". Not even one order of magnitude
faster, except, may be, vs Model 50 in artificial very
memory-light floating-point intensive scenarios.
High end S/360 (Model 65) came about half a year later. I would
imagine that for non-floating-point code it had about the same
speed as 6600.   

 
Those 360 models seem wrong.  The 360/50 was a midrange machine
that shipped in August 1965, the /65 was a large machine that
shipped in November 1964,  

>
Do you mean, November 1965? 

 
Yes, of course, I can't type.
 

and the 360/75 was a high end machine that
shipped in January 1966.  They were all announced at the same
time, give or take IBM's replacing the paper 60 and 70 with the
faster 65 and 75. 

>
Sorry, I did not read Wikipedia articles about /50 and /65 with
sufficient attention and confused announcement with shipment. Didn't
realize that for /50 the time between announcement and shipment was
much longer than for /65. 

 
With that correction, only three months which doesn't seem like much.
The physical planning for power and cooling and raised floors and
such to be ready for delivery would take longer than that.
 

According to Wikipedia:
Model Announcement Shipment A-to-S
50    1964-04      1965-08  18 months
65    1965-04      1965-11   7 months

W.r.t. CDC 6600 Wikipedia article does not state an exact date of the
1st shipment at all, just saying that it was in 1965. 

 
Says here late 1964. It was a huge embarassment to IBM. I imagine a
large part of that was that it blew up IBM's longstanding belief that
you had to make a computer really complicated to make it fast, viz.
STRETCH and 360/91. 
 
https://mncomputinghistory.com/control-data-corporation/
 

Probably, mncomputinghistory and Wikipedia have different definitions
of delivery.

IBM sort of came around to that with the 360/44, which implemented a
scientific subset of the 360's instruction set and ran nearly as fast
as a /65. It was intended for process control so they added priority
interrupts and some real time I/O.