"... 100+ GB ...combine rows...consolidated output..."

Life is hard - so perhaps you better go with sqlite?

See also Re: Reading HUGE file multiple times and Limits In SQLite.

Best regards, Karl

P.S.: And remember:

#!/usr/bin/env perl

use strict;
use warnings;
use feature qw(say);
use Try::Tiny;

# say $0;

try { ...; } catch { say $_}

__END__

karls-mac-mini:playground karl$ ./bfdi533.pl
Unimplemented at ./bfdi533.pl line 10.
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