Select Code to Download

sub set_column_widths {
    my $h         = shift; # reference to hash table of speeds, keyed 
+by datetime, then by database
...
        $databases->{$db} = $databases->{$db} > $l ? $databases->{$db}
+ : $l;  
    }
}

set_column_widths(\%h, \%db, \@db);

printf "%11s", $_ for (@db);

...
# stick a space between columns

printf " %$db{$_}s", $_ for (@db);

#!/usr/bin/env perl
use 5.010; use strict; use warnings;
...
server02: 2015-06-01T12:41:03-04:00  MYDB101                 7 MB/sec
server02: 2015-06-01T12:41:03-04:00  MYDB202                 7 MB/sec
server02: 2015-06-01T12:41:03-04:00  _OTHER_DB_             55 MB/sec