[email protected] (David Purdy) writes: > I honestly cannot remember MVS *EVER* supporting 3375’s DOS/VSE and VM > AFAIK are the only OS’s. Can someone correct me please ?
large corporations started ordering hundreds of vm/4300s at a time for placing out in departmental (non-datacenter) areas ... sort of the leading edge of the coming distributed computing tsunami. MVS was looking at playing in that market ... but the only (new) CKD dasd was 3380 (high-end datacenter) ... all the low & mid-range disks were FBA (3310 & 3370) that could be deployed in non-datacenter, departmental areas. https://www-03.ibm.com/ibm/history/exhibits/storage/storage_3370.html Eventually they came out with (emulated) CKD announced as 3375 to support MVS in that market ... however there was additional issue, the customers were looking at large number of unattended systems per support person ... as opposed to number of support persons per system. past posts mentioning CKD, FBA, multi-track search, etc. http://www.garlic.com/~lynn/submain.html#dasd there was also similar explosion of vm/4300s inside IBM ... at one point resulting in significant problem scheduling increasingly scarce conference rooms for meetings. trivia: 4341 integrated channels were so fast that with slight tweaking disk engineering & product test were using them for testing 3mbyte/sec 3880/3380 testing. 3370 & 3375 https://en.wikipedia.org/wiki/History_of_IBM_magnetic_disk_drives#IBM_3370_and_3375 above mention research starting on thin-film floating heads at TJR in the 60s. However, in the 70s, the disk division were running thin-film, floating head "air-bearing" simulation studies on SJR (bldg28, before research moved up the hill) MVT 370/195. However, even with high-priority designation, there were only getting a couple turn-arounds a month. Then bldg. 15 (product test) got early engineering 3033 for disk I/O testing. they had been been running all testing in bldg 14&15 "stand-alone" (at one point they had tried running under MVS but found it had 15min MTBF in that environment, requiring manual re-ipl). I then offered to rewrite I/O supervisor to make it bullet proof and never fail ... after which nearly all machines in bldg 14&15 ran under that system. Turns out even several concurrent I/O testing only used a few percent of 3033 CPU ... so started using the machine for lots of other stuff. We moved the air-bearing simulation from the MVT 370/195 to bldg 15 3033 and they could get several turn-arounds a day ... rather than a couple/month (while 370/195 was a little over twice the 3033 performance, the 195 job queue was measured in number of weeks). 1979 thin-film heads introduced for large disks http://www.computerhistory.org/storageengine/thin-film-heads-introduced-for-large-disks/ past posts getting to play disk engineer in bldgs 14&15 http://www.garlic.com/~lynn/subtopic.html#disk -- virtualization experience starting Jan1968, online at home since Mar1970 ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
