On 17 Dec 99, at 16:35, Gordon Bower wrote:
> Something strange happened, though. Version 19 slows down considerably
> more in response to my doing other low-demand things on my machine,
> reading email/web browsing/etc. Is this just in the nature of v19,
> something to do with the optimizations that were added to speed it up? (It
> does still average a faster rate in the long run).
Very likely this is the case. The new code is better tuned to the
hardware - making more efficient use of the cache - if something else
makes demands on the same cache, there's bound to be a hit of some
sort. I would guess that with a moderate load of active "normal"
applications on the system, v18 & v19 would run at about the same
speed. Of course, v19 would slow down more since it's starting at a
faster speed.
>
> As long as I am writing to the list -- perhaps someone could explain in a
> little more detail than readme.txt does as to what the valid range of
> values for the Priority variable are and what the effect of each is on NT
> and 95? I experimented a little by trial and error last summer when a
> friend running a 3-D screen saver offered to let me run the program on his
> machine, but we never had much success fine-tuning it so as to not
> interfere with his work.
The valid range is 0-15.
If you specify 0, you will lose half your CPU to the OS's native
cycle sink. This is probably not what you want.
Screen savers normally run at priority 4, normal applications at 8.
If you set a CPU-intensive program to run above priority 8, your
"normal" activities will be badly impacted. If you go above 10 or 11,
you can expect to start to get problems with device drivers for
modems etc. If you try 14 or 15, you will very likely lose control of
your system altogether.
If you really need to run a screensaver as well as Prime95, I'd
reccomend setting Prime95 at priority 4 so that it shares cycles
about equally with the screensaver.
Regards
Brian Beesley
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