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Old April 26th 05, 11:07 PM
Richard Clark
 
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On Tue, 26 Apr 2005 08:35:35 -0700, "Joel Kolstad"
wrote:

Good point, although in the case of highly sophisticated CPUs (superscalar,
VLIW, etc.), the difficulty in getting all the cache and register access
scheduling optimal is difficult enough that there are typically very few
people who can consistently do better in assembly than a high level language
with an optimizer.

In many cases selecting a better algorithm might buy one a lot more!


Hi Joel,

Almost every performance gain you describe is hardware limited - not
software limited. If you can conspire to make every reference call a
cache hit, you win, but 99.999% of the applications used by everyone
here (including antenna modeling) fail in that one regard and stumble
over the rest of the "optimizations." When I look at my performance
monitor, it is idling along at 0 to 2% usage as I type (no surprise).

When I pull up a page from the New York Times (before I set my
firewall filters to turn off advertising) it would peg at 100% ad
infinitum (I guess there's an ironic pun in that). I dare say that no
one is using optimized code for running Nike ads - or if they are,
that it makes any appreciable difference at 2GHz (with a memory access
running at, what, 10% of that?). What HAS been optimized is the data
compression schemes that make up for sloppy code (the problem is
undoubtedly a memory leak or a failed garbage collection routine).

In a sense, I used client side optimization to kill the advertising
stream.

73's
Richard Clark, KB7QHC