shmuel+ibm-m...@patriot.net (Shmuel Metz , Seymour J.) writes: > You really mean 709 and not 7090? That's a big jump!
re: http://www.garlic.com/~lynn/2011k.html#8 Last card reader? univ. supposedly had something like #3 709, thousands of tubes that constantly required maintenance ... something like "20 ton" air conditioning capacity. much of workload was student fortran ibsys running tape-to-tape (second or two elapsed) ... with 1401 front-end for unit record (carried tape between 709 drives and 1401 drives) there was intermediate step replacing 1401 with 360/30 ... started out with 360/30 running hardware emulation for the MPIO that did the unit-record<->tape. I got student job rewritting MPIO in 360 assembler .... got to design my own stand-alone monitor, interrupt handlers, device drivers, console interface, etc. then move to os/360 on 360/65 (actually 360/67 spent most of the time running as 360/65, replaced both 709 & 360/30) ... much less heat. student jobs then ran 3step fortran-g, complie, link-edit, & go ... over a minute elapsed time per student jog; hasp got it down to over 30+ seconds elapsed time. I started taking stage-2 sysgens completely apart and put them back together for careful ordering of files and pds members to optimize arm seek ... getting down to a little under 13seconds elapsed time (nearly three times improvement) it wasn't until univ. installed watfor that student job elapsed time got down to 709. the univ. was supposedly getting 360/67 to run tss/360 ... but tss/360 failed to reach any reasonable operational level. eventually did get (virtual machine) cp67 january 1968 ... and the univ. let me play with it on weekends. I rewrote large sections of cp67 before graduating. -- virtualization experience starting Jan1968, online at home since Mar1970 ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
