Some optimization results

Ozan Yigit oz at yunexus.yorku.ca
Wed May 15 04:57:33 AEST 1991


Dan Bernstein writes:

>On any given bottleneck, someone could either do the obvious big
>optimizations and stop, or do every optimization that he can see that
>will gain a few percent.

An unreliable, non-universal few percent is almost never worth the
unreadable, unmaintainable mess that is produced as an end result of
"every optimization", given a sufficiently well-written program to
start with.

>I can keep pointing out how hand optimization gives huge speedups.

 wollman at emily.uvm.edu (Garrett Wollman) points out elsewhere:

 | [For example, yabba will not work for (some subset of the set of)
 | large binary files on our SGI 4D/340S.  Dan also spent so much effort
 | unrolling loops that the source is nearly incomprehensible, and breaks
 | a parallelizing preprocessor which can be used by the MIPS/SGI
 | compiler to great effect.]

... oz
---
In seeking the unattainable, simplicity | Internet: oz at nexus.yorku.ca
only gets in the way. -- Alan J. Perlis | Uucp: utai/utzoo!yunexus!oz



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