#1: I really doubt this is your problem. Perl's regex engine contains very smart optimizations for doing this kind of match.

#2: How big is "the whole code"? I'm curious about what eval() and evalTree() do. When you say this sub has 95% of the runtime is that inclusive of these sub-calls or exclusive? If it's inclusive then your problem could very well actually be due to what happens in them...

UPDATE: Looking closer, I'm really curious about that eval() call. As it's written it doesn't make sense - Perl won't let you call a builtin with that syntax: 

  $ perl -e 'eval->(print "foo\n")'
foo
Undefined subroutine &main:: called at -e line 1.

[download]

That made me think you must not be using the real Perl eval() builtin. But now I wonder if you made a typo and your code actually is using the eval() builtin. If that's the case then you can stop searching, I know exactly why your code is so slow! String eval() is very slow in Perl - it's actually compiling your code each time it's run!

UPDATE 2: My mistake, Perl is apparently ok with that syntax for calling string eval(): 

   $ perl -e 'eval->(qq{print "foo\n"})'
    foo

[download]

-sam

In reply to Re: optimization help by samtregar
in thread optimization help by GSF

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