>>> Those drivers have been tested with HZ==100, but probably not
>>> with any other value. Also if HZ is made very large (e.g.
>>> microsecond accuracy) "defer as short as possible" is the wrong
>>> behaviour.
>>> So IMHO those 1s should all be changed to HZ/100.
>> 1 jiffie != 1 s
> HZ/100 = 10ms which is a reasonable appr. for a 18.2ms jiffy
> (ix86)
If a jiffie is indeed 18.2ms then HZ/100 is a good approximation
to HALF a jiffie and HZ/50 a good approximation to one jiffie.
However, the standard used by MSDOS (which I assume is what you're
referring to) is for the clock to tick ~18.2 times per second (to
be more accurate, 65536 ticks per hour), in which case the correct
definition would be that a jiffie is 5*HZ/91 and it can be
approximated by HZ/18 - which is a long way from HZ/100 !!!
Q> # echo '12k 65536 3600 /p' | dc
Q> 18.204444444444
Q> #
The above says "To 12 decimal places, show me the result of dividing
65536 by the 3600 seconds that make up an hour"...
Best wishes from Riley.
+----------------------------------------------------------------------+
| There is something frustrating about the quality and speed of Linux |
| development, ie., the quality is too high and the speed is too high, |
| in other words, I can implement this XXXX feature, but I bet someone |
| else has already done so and is just about to release their patch. |
+----------------------------------------------------------------------+
* ftp://ftp.MemAlpha.cx/pub/rhw/Linux
* http://www.MemAlpha.cx/kernel.versions.html
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/