The following message is a courtesy copy of an article that has been posted to bit.listserv.ibm-main,alt.folklore.computers as well.
r...@velocitysoftware.com (Rich Smrcina) writes: > Most of the new support now centers around capacity (very large > virtual machines) and virtual networking (virtual switch). There is a > statement of direction for clustering (not sysplex) and guest > migration (moving live machines between VM systems). All of this with > the intent of supporting Linux. note that some of the commercial (virtual machine) timesharing service bureaus had done moving live machines between VM systems in the early 70s, it was combination of 7x24 operation and providing services to customers around the world .... addressing problem that there was no down period for service ... where downtime/outages could be tolerated for things like preventive maintenance. They would migrate virtual machines as part of dynamically taking complexes offline (out of the cluster)for service. misc. past posts mentioning the virtual machine commercial timesharing services dating back to 60s: http://www.garlic.com/~lynn/subtopic.html#timeshare The largest such of the clustering ("single system image") operations in the late 70s (not limited to vm systems, but any mainframe complex, anywhere) was the US VM-based internal (worldwide) sales&marketing support HONE system that. The US HONE centers had been consolidated in bldg. (they no longer occupy the bldg, but it is located next door to the new facebook bldg ). This US datacenter was the largest (although other HONE clones had started to spring up several places around the world) with load-balancing and fall-over recovery. Then because of earthquake concern, in the early 80s, the cal. center was first replicated in Dallas and then a 3rd in Boulder (with load-balancing and fall-over across the redundant centers). a few recent posts in "Greater IBM" discussing HONE: http://www.garlic.com/~lynn/2010d.html#27 HONE & VMSHARE http://www.garlic.com/~lynn/2010e.html#24 Unbundling & HONE http://www.garlic.com/~lynn/2010e.html#25 HONE Compute Intensive http://www.garlic.com/~lynn/2010e.html#29 HONE & VMSHARE misc. ohter posts mentioning HONE http://www.garlic.com/~lynn/subtopic.html#hone The product to customers saw big impact when POK got the development group shutdown and all the people moved to POK to support MVS/XA development. initially the product was also killed, Endicott managed to save the product mission... but had to reconstitute a group from scratch. This possibly contributed to the VM/SP quality mentioned in Melinda's history ... recent reference: http://www.garlic.com/~lynn/2010e.html#31 What was old is new again (water chilled) http://www.garlic.com/~lynn/2010e.html#36 What was old is new again (water chilled) The 4331/4341 saw big explosion in distributed machines connected via network ... so the (their new) focus wasn't on the highend and/or clustering in single location. There was a research clustering project, eight 4341s with 3088 ... that eventually offered as product ... but that ran into a couple problems 1) there was already pressure from high-end (mvs, 3033, 3081s, etc) where customers found that multiple vm/4341s were much more cost effective than the big iron ... so anything that enhanced this, was met with opposition. 2) the internal product had things like cluster-wide operations taking very small subsecond elapsed time. however, for product ship they were forced to move to SNA ... and all of a sudden simple cluster-wide coordination operations were taking nearly a minute elapsed time. This is similar to the on-going SNA battles that my wife faced when she had been con'ed into going to POK to be in charge of (high-end) mainframe loosely-coupled architecture. The battles with SNA (ephemeral temporary truces where she could use anything she wanted with datacenter walls but SNA had to be used by anything crossing the walls of the datacenters) and very little uptake at the time (except for IMS hot-standby until sysplex) met that she didn't stay long ... misc. past posts mentioning her peer-coupled shared data architecture http://www.garlic.com/~lynn/submain.html#shareddata -- 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
