New theory: the fork is failing with EAGAIN or ERESTARTNOINTR.
To prove fork is not failing, add the following line immediately before the open my $IN, '<', $infile or exit(0); line. 

defined $pid or die "fork failed $!";

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In reply to Re: Script exponentially slower as number of files to process increases by tybalt89
in thread Script exponentially slower as number of files to process increases by xnous

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