!/usr/bin/perl
use strict;
use warnings;
my $file_in='test.txt';
my $file_out='test.out.txt';
my @data;
{
  open(my $fh, '<', $file_in) or die("ERROR open $file_in ($!)\n");
  while(my $line=<$fh>)
  {
    push(@data,$line);
    if(my ($name)=$line=~/(\w+)\.xml\.gz/)
    { push(@{$order{$name}},$#data); }
  }
  close($fh);
}

for my $arr (values(%order))
{
  while(@$arr>2)
  {
    my $pos=shift(@$arr);
    splice(@data,$pos,1);
  }
}

{
  open(my $fh, '>', $file_out) or die("ERROR open $file_out ($!)\n");
  print $fh @data;
  close($fh);
}