[TUHS] Old mainframe I/O speed (was: core)

Norman Wilson norman at oclsc.org
Mon Jun 25 04:49:30 AEST 2018

Paul Winalski:

  Rather than design a new
  CPU, they just put NOPs in the Skipjack microcode to slow it down.
  The official code name for this machine was Flounder, but within DEC
  engineering we called it "Wimpjack".  Customers could buy a field
  upgrade for Flounder microcode that restored it to Skipjack
  performance levels.


As I remember it, once it came out that the upgrade
merely removed gratuitous nops, customers raised sufficient
fuss that the denopped microcode was made available for
free (perhaps only to those with service contracts) and
Flounder (VAX 8500) was no longer sold.

Norman Wilson
Toronto ON

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