Killer Micro Question

Barry Shein bzs at world.std.com
Thu Nov 15 12:07:25 AEST 1990


> Suppose you wanted a system to manage huge databases.  You needed strong
>integrity controls for concurrent database updates.  You needed to access the
>data in a huge room packed to the gills with disk drives.  You needed to be
>able to access the same data from any CPU in the system.  You couldn't
>tolerate the performance hit of the bottleneck caused by pumping all the data
>down an ethernet.

No, but FDDI runs at near bus speeds, so you're talking old technology
for an application like this. IBM/370 drives run at about 5 MB/s max,
not much a challenge for fiber, tho the software can be challenging
for other reasons. Most of the advantage of IBM mainframes is that
they *are* a distributed operating system, disk channels have
significant processing power. One can do things like send a disk
channel off looking for a database record and go back to something
else until the answer is found. So we're sort of talking in circles
here.

> IBM didn't get that big by ignoring its customers' needs and forcing
>them to buy an excessively expensive and underperforming system.
>Instead they carefully monitored those needs, and evolved their
>hardware and software to meet them.

That's an interesting theory.
-- 
        -Barry Shein

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