python speed

Harald Armin Massa haraldarminmassa at gmail.com
Wed Nov 30 17:34:47 CET 2005


>Faster than assembly? LOL... :)

why not? Of course, a simple script like "copy 200 bytes from left to
right" can be handoptimized in assembler and run at optimum speed.
Maybe there is even a special processor command to do that.

I learned that there was one generation of CPUs which had effectively a
command to copy X bytes from left to right; but a specific version of
that CPU did this command slower then a loop in certain situations.
Some newer generations of that CPU and even some competitors CPU had
that command implented correctly, and it was indeed faster than the
loop.

Now: is it rather likely that for a single programm a programmer is
able to get it right for all CPUs?

It even gets more complicated. The human mind is able to consider a
certain amount of things at once, sth. like on-chip-cache or
short-term-memory.

Now with an ever growing complexity of processors, with cache lines,
partyparallelexecution, branchprediction, out of order execution,
multilevelcaching, hypermetathreading ... it may be that the usual
availaible human brain is no longer capable of really knowing what
happens.

My guess is that the average code speed of a Rigopy could indeed be
higher than the average code speed of the average assembler programmer.


Harald




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