14 Nov
2005
14 Nov
'05
11:48 p.m.
On Mon, 14 Nov 2005 13:33:01 -0600
Jim Battle <frustum at pacbell.net> wrote:
woodelf wrote:
...
Well, probably on said modern PeeCee, you could run eight or ten instances of the emulator
without bogging the machine down. What degree of 'nice' (I know it doesn't
exist in windoze, just wondering about the equivalent thing) does the emulator run at?
The PC probably still has all the dancing, flashing foolishness that gatesware implies
running in addition to the emulator.
Having got a new PC ... 2 GHZ??? who knows the
real speed.
I have tried Spare time gizmos - pdp 8 emulator ( A minor bug
-- with windows how do you get the bell to sound ?).
I was running some sort of diagnostics and had the RTC displayed
and for about 10 minutes of real time, the clock advanced a hour.
That must be at least 6x faster than the real thing on this computer.
If a 2 GHz (give or take) x86 CPU emulates a pdp 8 at 6x, it means either the
code is inefficient, or the code contains a speed regulator that doesn't work
properly.
The original PDP-8 took 10 clocks at 1 MHz to execute one instruction, a 2 GHz
CPU has 20 million cycles to interpret one instruction. So at 6x realtime, the
program is using 3.2 million cycles to interpret one instruction.