Do you want me paste code where split() taking more {blah}

I want you to post code -- directly comparable to the OPs -- where doing something takes longer than doing nothing.

But, if you really want to play, show me code that filters a 2 million line x 11 TAB separated fields, file on the value of a field whose number and filter value I supply on the command line, more quickly than:

#! perl -slw
use strict;
use Time::HiRes qw[ time ];

our $FNO //= 6;
our $V   //= 500;

my $start = time;
my @filtered;

while( <> ) {
    my @fields = split( "\t", $_ );
    $fields[ $FNO ] == $V and push @filtered,$_;
}
printf "Took %f seconds\n", time() - $start;
printf "Kept %u records\n", scalar @filtered;

__END__
C:\test>1036737 -FNO=6 -V=500 < numbers.tsv
Took 19.072147 seconds
Kept 2005 records

C:\test>1036737 -FNO=6 -V=500 < numbers.tsv
Took 19.021369 seconds
Kept 2005 records
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