Military Time 2900
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Well your problem was that you were using a 68030. Workloads are a different issue from single app time...
Gene Cash
note that the 360 just had the cpu timer (at location 80) ... and everything else was done in software.
370 introduced the tod clock, the clock comparator, and provided a new cpu timer that wasn't in memory (and over the years, the location 80 cpu timer was eliminated).
Charlie Gibbs Yes a sad tale indeed. Irving Gould and Mehdi Ali milked Commodore and...
the clock comparator was a tod clock value ... that when the comparator and the tod value match ... generated an interrupt.
one of the issues with the location timer was that you wouldn't loose clock tics with the overlapping MVC gimick ...
the clock either tic'ed the old value or the new value ... but a tic wasn't lost.
with the new cpu timer ... there were separate instructions to store the current value and set a new value ... and the timer could "tic" between a store and a set (which would loose a tic). cp67 had been fairly scrupulous for accounting for all timer tics.
then there was also the cpu meter ... which was used for billing processor ... from the days when processors were leased. there was typically 4-shift billing schedule (i.e. 3-shift weekdays, and the weekend) ... with 3rd and 4th shift being billed (under leases) at possibly 1-10th 1st shift billing.
I like to think that part of the problem was that the heads at Commodore didn't think so either. I picture them sitting...
one of the "great" cp67 hacks was the use of prepare ccw on terminal i-o. normally the cpu meter ran when either the processor was running and-or there was "active" i-o.
cp67 was being pushed as time-sharing service ... and some number of commercial operations had spun-off to use it as base for commercial time-sharing service
one of the issues was leaving the system up and operational 24x7 ... however, off-shift use could be relatively sporadic ... with accounted-for-use not covering the lease billing (based on cpu meter running constantly, even when cpu wasn't active ... and just waiting for terminal i-o). you could save off-shift costs by running dark room with no operators present ... but even at 1-10th billing, it could be difficult to recover sufficient accounting to cover the billing costs.
the "great" cp67 hack using prepare ccw on terminal i-o ... was that prepare ccw would suspend waiting for terminal character to be received ... but not be treated as an active i-o by the cpu meter. this change significantly reduced unrecoverable costs of providing off-shift, always up, 7x24 time-sharing service (system sitting idle and available waiting for somebody to dial-in, or people were dialed-in ... but thinking at the moment).
Gene Cash originally, why i don't know. 360-67 had high-resolution timer option .... 13-some mic. version for use in accounting and time-slice. cp67 would stuff value for something 50millseconds at location...
going into 370 time-frame, you were starting to see more and more purchased system ... so that unaccounted for (leased) billing was becoming less and less of an issue. however, another characteristic of the cpu meter was that it would "coast" for 400 milliseconds after the last event that caused it to run.
for trivia question ... which mainframe operating system had a system event that woke-up every 400 milliseconds?