[email protected] (David Andrews) writes: > That tickles a neuron. Was there not a "RASP" component to OS/VS1 > JES?
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 http://www.garlic.com/~lynn/2014i.html#67 z/OS physical memory usage with multiple copies of same load module at different virtual addresses RASP was virtual memory & virtual filesystem for MFT-II. the person responsible left and was hired by one of the large clone processor companies where he re-implemented it from scratch. even though IBM wasn't going to do anything with it ... they still sued the clone company (for lifting ibm code) and the court had people do detail review of the new code. Foklore is that possibly only 2-3 trivial sequences of code were found that could be considered similar. I don't have any recollection of RASP in OS/VS1 JES. I do remember talking to the JES2 group about enhancing shared spool. There were a huge amount of enhancements to VM370 for the internal world-wide sales&marketing support HONE system (very little shipping to customers before corporate hdqtrs was constantly trying to kill off vm370) ... some past posts http://www.garlic.com/~lynn/subtopic.html#hone part of this was cluster, single-system-image system ... at one time the US HONE datacenter in silicon valley had the largest single-system-image operation in the world, load balancing and fall-over/recovery across all the machines in the complex. The closest thing that came to it was ACP/TPF loosely-coupled operation ... but at the time ACP/TPF didn't have tightly-coupled support ... while VM370 had SMP support ... so could have max. loosely-coupled configuration of max. sized tightly coupled CECs. Standard OS/360 and ACP/TPF had started out using shared device reserve CCW, then do the I/O channel program, then do device release CCW. ACP/TPF got a special RPQ for 3830 disk controller "logical locking" ... that used memory in the 3830 allowing definition of logical locks ... for serializing logical operations w/o going through the overhead device reserve/release. The problem cropped up tho with string-switch architecture where multiple different 3830s had concurrent access to the same disk, lock memory in one 3830 would be consistent with lock memory in another 3830 for the same logical operation. The HONE system for loosely-coupled shared disk operation used a CKD "compare-and-swap" CCW sequence (one of the rare cases where CKD actually proved some benefit over FBA). Data was read from disk, updated in memory ... and a "search data equal" CCW (aka compare) was used ... if it didn't match, it failed ... however if it succeeded it would do a write operation. Note: later in the early 80s, HONE extended its cluster SSI across geographically separated datacenters, with a 2nd datacenter in Dallas and then a 3rd datacenter in Boulder. Had some meetings with people from JES2 group about enhancing JES2 shared spool to also utilize compare-and-swap CCW sequence. other trivia, Charlie had invented compare-and-swap instruction when he was working on fine grain multiprocessor locking for cp67 at the science cneter (mnemonic chosen because CAS are his initials). Attempts to get it into 370 architecture were initially rebuffed because the POK favorite son operating system people claimed that test&set was sufficient. Challenge was in order to get compare-and-swap into 370, had to come up with non-multiprocessor uses (examples still are included in principles of operation). some past posts http://www.garlic.com/~lynn/subtopic.html#smp past posts mentioning aspen (clone vendor's name for rasp): http://www.garlic.com/~lynn/2000f.html#69 TSS ancient history, was X86 ultimate CISC? designs) http://www.garlic.com/~lynn/2001g.html#35 Did AT&T offer Unix to Digital Equipment in the 70s? http://www.garlic.com/~lynn/2002i.html#63 Hercules and System/390 - do we need it? http://www.garlic.com/~lynn/2004q.html#37 A Glimpse into PC Development Philosophy http://www.garlic.com/~lynn/2005p.html#44 hasp, jes, rasp, aspen, gold http://www.garlic.com/~lynn/2005q.html#26 What ever happened to Tandem and NonStop OS ? http://www.garlic.com/~lynn/2005q.html#27 What ever happened to Tandem and NonStop OS ? http://www.garlic.com/~lynn/2006f.html#26 Old PCs--environmental hazard http://www.garlic.com/~lynn/2006w.html#24 IBM sues maker of Intel-based Mainframe clones http://www.garlic.com/~lynn/2006w.html#28 IBM sues maker of Intel-based Mainframe clones http://www.garlic.com/~lynn/2007m.html#69 Operating systems are old and busted http://www.garlic.com/~lynn/2010i.html#44 someone smarter than Dave Cutler -- 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
