On Monday,  9 April 2001 at 19:44:27 -0600, Rick Kelly wrote:
> Greg Lehey said:
>> Tandem's Integrity series had a thing called triple modular
>> redundancy: they saved one processor and voted three ways.  Each
>> processor was on a separate hot-pluggable board, so you could repair
>> the CPU while it was running.  The Tandem proprietary NonStop
>> processors were not as sophisticated: they checkpointed data across a
>> high-speed bus, but they only had a single processor per CPU.  They
>> were also hot-pluggable.
>
> When I worked for Progress Software, we had to crash systems to test
> the Progress database recovery tools. Tandem systems are very hard to
> crash.

Pulling a CPU does it every time :-)

Greg
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