The following message is a courtesy copy of an article that has been posted to bit.listserv.ibm-main,alt.folklore.computers as well.
shmuel+ibm-m...@patriot.net (Shmuel Metz , Seymour J.) writes: > Wasn't VM/SP also an add-on to VMF/370 R6? I know for sure that MVS/SP was > an addon to OS/VS2 3.8 + SU64 et al, and I vaguely recall that it wasn't > until around ESA 4 that the free MVS base went away from the packaging. re: http://www.garlic.com/~lynn/2010d.html#43 What was old is new again (water chilled) http://www.garlic.com/~lynn/2010d.html#45 What was old is new again (water chilled) http://www.garlic.com/~lynn/2010e.html#28 What was old is new again (water chilled) Melinda Varian's home page http://www.princeton.edu/~melinda/ from her VM history document at above ("VM/SP becomes a new base with all the sepp/bsepp stuff"): At the same time, we started seeing the results of IBM's new commitment to VM. VM System Product Release 1 came out late in 1980. VM/SP1 combined all the [B]SEPP function into the new base and added an amazing collection of new function (amounting to more than 100,000 lines of new code): XEDIT, EXEC 2, IUCV, MIH, SUBCOM, MP support, and more. ... snip ... also from above: VM/SP1 was just amazingly buggy. The first year of SP1 was simply chaotic. The system had clearly been shipped before it was at all well tested, but the new function was so alluring that customers put it into production right away. So, CP was crashing all over the place; CMS was destroying minidisks right and left; the new PUT process was delaying the shipment of fixes; and tempers were flaring. When the great toolmaker Jim Bergsten produced a T-shirt that warned "VM/SP is waiting for you", his supply sold out immediately. ... snip ... I still have the t-shirt. somewhat related other old stuff Date: 02/17/81 11:18:51 From: wheeler re: cia vm/sp experience; YKT has seen similar performance problems going to SP. They have isolated a major compenent of it tho. It turns out that SP increased the default terminal I/O control block size for all terminals in a redesign for new terminals. This increase in size resulted in the block no longer being in the "sub-pool" size range. A storage request for for a sub-pool size block can be satisfied in less than 30 instructions. A non sub-pool size block is allocated using the a best fit free storage allocation algorithm (i.e. everything on the chain must be scanned). A large system can easily have 1,000 blocks or more on the chain. It takes 5-6 instructions per block. Re-defining sub-pool sized blocks in DMKFRE (modification & re-assembly) resulted in almost returning overhead to release 6 days. There are other significant SP degradation hits that have to do only with real AP/MP operations. ... snip ... other old email on the subject http://www.garlic.com/~lynn/2003c.html#email790329 in this post http://www.garlic.com/~lynn/200ec.html#35 diffence between itanium and alpha and http://www.garlic.com/~lynn/2006y.html#email791011b in this post http://www.garlic.com/~lynn/2006y.html#0 Why so little parallelism? another old email discussing performance problems at same customer http://www.garlic.com/~lynn/2001f.html#email830420 in this post http://www.garlic.com/~lynn/2001f.html#57 any 70's era supercomputers that ran as slow as today's supercomputers? the above is related to custom MP changes made to support TPF ... but caused performance degradation for all other customers ... which was then somewhat offset by improvement/changes in 3270 i/o (modulo the storage subpool "bug") ... which didn't help at the above customer since they weren't using 3270s ... but lots of ascii glass teletypes. recent post mentioning changes done for TPF: http://www.garlic.com/~lynn/2010e.html#23 Item on TPF misc. past posts also mentioning the above email http://www.garlic.com/~lynn/2006u.html#37 To RISC or not to RISC http://www.garlic.com/~lynn/2006v.html#6 Reasons for the big paradigm switch http://www.garlic.com/~lynn/2006y.html#10 Why so little parallelism? http://www.garlic.com/~lynn/2006y.html#36 Multiple mappings http://www.garlic.com/~lynn/2008d.html#42 VM/370 Release 6 Waterloo tape (CIA MODS) http://www.garlic.com/~lynn/2008j.html#82 Taxes http://www.garlic.com/~lynn/2008m.html#22 Future architectures http://www.garlic.com/~lynn/2009p.html#37 Hillgang user group presentation yesterday http://www.garlic.com/~lynn/2009s.html#0 tty http://www.garlic.com/~lynn/2010d.html#14 Happy DEC-10 Day -- 42yrs virtualization experience (since Jan68), 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
