Corion is right with his suggestions. If you're still interested in how to speed up the regex, here it goes:

The first .+ will first match all characters, then gives up characters until the \t finds the first tab, then the second .+ has no more character to match, then the first .+ has to give up characters again etc.

To avoid all that backtracking, you should substitute each .+ by something that matches everything except tabulators, [^\t]+.

In reply to Re: Suggestion for regular expression speed improvement. by moritz
in thread Suggestion for regular expression speed improvement. by bala.linux

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