But it will be hugely slower than doing a simple search to find the embedded IP and then look that up in a hash that contains the 500 IPs in question.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco.
Rule 1 has a caveat! -- Who broke the cabal?

In reply to Re^2: Efficient Way to Parse a Large Log File with a Large Regex (with Regexp::Assemble) by BrowserUk
in thread Efficient Way to Parse a Large Log File with a Large Regex by Dru

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