On 4/11/25 12:20, Dan Greiner wrote:
As to Charles' statement that "STCKF is potentially so much faster ...", well, that depends. STCK and STCKE are required to produce monitonically-advancing results. That is, they will never produce the same results in an MP environment, and the results will always increase (at least until the STCK results wrap around in around 2042). To do this, the CPU may delay the results of the execution of a STCK until it can produce an advancing value. This could be a longer delay in a configuration with lots of CPUs; not so long a delay in a configuration with fewer CPUs.
... Don't distinct values in the Programmable Field remove the need for inter-processor serialization?
But could an STCK(E) by a processor with a lower Programmable Field appear incorrectly to come before a STCK(E) performed earlier by a processor with a higher value? Could any program ever detect that? -- gil
