On Jun 8, 2014, at 1:08 AM, Mike Alexander wrote:
I do know the answers to some of these questions (as I'm sure Gary does too). Comments appear below. They were somewhat hastily entered so may have mistakes.
--On June 7, 2014 at 9:28:49 PM -0400 Jeff Ogden <email@example.com> wrote:
And what was the hardware evolution of the disks? Did MTS ever use
2311s? I'm sure that 2314s were used. I assume that that was followed
by 3330s, 3330-IIs, and then 3350s. Were 3350s the first
non-removable disks (ignoring the 2301 drum and 2305 fixed head file)
we used? We had various brand-X disks (ITEL, Memorex, Amdahl, ...),
but I think they were all compatible with some model of IBM disk.
Were the Amdahl disks the first to have a native mode of their own or
at least the first to have a native mode that we used?
The first disks were 2311s. I think we used all the others you mention as well as a few oddball ones. Do you remember the super disk with for spindles and one actuator in a large case. MTS drove it so hard that it essentially melted and we were down for several days while the vendor (I forget now who it was) flew in a new one.
These disks all emulated IBM disks, but some also had a native mode which MTS could use. This wasn't common, and I can't remember the details, but I'm sure there are tables in the distributions that would fill in some of these blanks.
Did I miss anything? What came after the Amdahl disks?
More IBM disks, probably 3390s of some flavor. By then we were very definitely an all-IBM shop.
On Jun 8, 2014, at 1:23 PM, Mike Alexander wrote in response to several comments and questions from Jeff:
On Jun 8, 2014, at 10:34 AM, Jeff Ogden wrote:
. . .
I know the file routines supported FBA [fixed block architecture] devices. Did U-M ever have any FBA disks?
Yes, we had support for several FBA devices. It wasn’t hard since the file system used a fixed block size by then.
Now that you mention it, I do remember the "super" disk. I think it was a 8800 from STC.
See: History: Milestones in HDD Capacity
A 1977 Computer World article on the STC Superdisk: http://books.google.com/books?id=gLYekwssyhsC&pg=PA44&lpg=PA44&dq=stc+superdisk&source=bl&ots=g55LG6CirG&sig=FaLIN0UWUB_jGKtTESBL41cA-MA&hl=en&sa=X&ei=I1eUU_TbLpSzyATtgIL4DA&ved=0CDUQ6AEwAg#v=onepage&q=stc%20superdisk&f=false
An October 1973 ad for the Super Disk: http://books.google.com/books?id=qYmeRiv3ZxgC&pg=PT4&lpg=PT4&dq=stc+superdisk&source=bl&ots=TaXWwBRsPy&sig=2Nhnk7a3EKaHy4l5kKpFAgmovmo&hl=en&sa=X&ei=I1eUU_TbLpSzyATtgIL4DA&ved=0CDcQ6AEwAw#v=onepage&q&f=false
That same issue of Computerworld has an article about the Superdisk on page 1. There were two models, the largest of which had a capacity of 800 MB, which was quite large for the time.