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To: (Jimmey Todd)
Subject: Re: Flex performance question
In-reply-to: Your message of Thu, 19 Feb 1998 11:01:17 PST.
Date: Thu, 19 Feb 1998 08:48:51 PST
From: Vern Paxson <vern>

> What I have found, is that the smaller the data chunk, the faster the
> program executes. This is the opposite of what I expected. Should this be
> happening this way?

This is exactly what will happen if your input file has embedded NULs.
From the man page:

A final note: flex is slow when matching NUL's, particularly
when  a  token  contains multiple NUL's.  It's best to write
rules which match short amounts of text if it's  anticipated
that the text will often include NUL's.

So that's the first thing to look for.