54 Processors

my wife did her stint in pok in charge of loosely-coupled architecture, where she came up with peer-coupled shared-data architecture (ims hot standby used some of it ... but you really didn't see it until parallel sysplex)

she also fought some battles over trotter-3088 channel-to-channel product (was sort of a bus&tag ctca switch with eight channel interfaces) for some advanced features ... that she lost.

sjr had a number of vm370 based projects ... including the original relational database & sql work was done on vm370 platform

which finally resulted in some tech. transfer to endicott and eventually released as sql-ds. there was a subsequent transfer of sql-ds from endicott back to stl resulting in (mainframe) db2.

in the early 80s, sjr also eventually got a trotter-3088 and did some hardware enhancements ... along the lines of my wife's original objectives. they put together an eight-way vm cluster using peer-to-peer protocols. things like going from zero to full cluster consistency was a subsecond operation.

attempting to get the support into the product path ... they were told that they would have to move the implementation from an underlying peer-to-peer protocol ... to a half-duplex lU6.2 based protocol. The LU6.2 implementation (running on the exact same hardware) resulted in the subsecond consistency operation increasing to something like 30 seconds elapsed time (because of the enormous latencies that were introduced when going from a full peer-to-peer operation to LU6.2 based infrastructure).

slightly related postings when my wife worked on fully peer-to-peer networking architecture specification (but ran into huge amount of pushback from the SNA forces):

we later did the ha-cmp project

during the ha-cmp days ... i was asked to author part of the corporate continuous availability strategy document; unfortunately both POK and Rochester complained that at the time, they couldn't meet the requirements and much of that section was dropped. in this time frame, we had coined the terms disaster survivability and geographic survivability to distinquish from straight disaster recovery

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