re: http://www.garlic.com/~lynn/2014i.html#66 z/OS physical memory usage with multiple copies of same load module at different virtual addresses
a little more topic drift. part of the MVT storage allocation issues was with contiguous storage allocation. quite a few customers were convinced to order 360/67 (very similar to 360/65 but with the addition of virtual memory) to run with tss/360. http://en.wikipedia.org/wiki/TSS/360 above has references to TSS/360 supporting position independent code. while tss/360 had lots of novel new stuff ... it never quite reached production quality ... so almost all customers run it with something else. lots of them just used it as 360/65 running os/360. however, the science center http://www.garlic.com/~lynn/subtopic.html#545tech ported cp40 to it for cp67 ... cp40 had originally been done on 360/40 with special hardware modification to support virtual memory http://www.garlic.com/~lynn/cp40seas1982.txt Unif of Mich ... did MTS ... later migrated to 370 (and some number of other univ. ran) http://en.wikipedia.org/wiki/Michigan_Terminal_System Stanford did Orvyl (where Wylburiginates). http://en.wikipedia.org/wiki/ORVYL_and_WYLBUR Boeing Huntsville got a 360/67 duplex which they ran with two separate systems with os/360. They original had gotten 360/67 for operating long-running 2250 graphic display jobs. They modified the 2nd release of MVT (os/360) for limited virtual memory support ... didn't do any paging ... same amount of virtual memory as real memory ... but capable of re-arranging memory to compensate for long running os/360 jobs resulting in storage fragmentation (using address translation, they could re-org memory addresses to get around a lot of MVT storage fragmentation). note that CICS had similar problems with OS/360 ... but addressed it by grabbing glob of storage and running its own scheduling, dispatching, memory management, and other system services ... to get around problems with base OS/360 services. Boeing Huntsville needed much of os/360 system services with lots of different long running 2250 graphic display tasks. -- virtualization experience starting Jan1968, online at home since Mar1970 ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
