| From: Akim Demaille <[EMAIL PROTECTED]>
| Date: 26 Apr 2000 18:41:32 +0200
|
| If you concentrate the measure on this very script, the performance
| penalty is frightening:
|
| It certainly is. This is a performance bug in mawk.
| I observed the bug in mawk 1.3.3.
|
| To work around the problem somewhat, please try replacing this:
|
| while (sub(/__oline__/, oline))
| continue
|
| with this:
|
| if ($0 ~ /__oline__/)
| while (sub(/__oline__/, oline))
| continue
!!!
I don't understand this at all. The performance loss is precisely
there, you don't even have to apply the same transformation to the
other patterns.
Hm, I see, what's really expensive is the fact that `oline' is
changing: if you remove `oline++' it flies again. I suppose it means
it has to recompile something for each value of `oline', but I don't
understand why recompiling a regex or something is needed when the lhs
of a s/// is changed.
Thanks for the cure, I'll apply it right now.
Akim
