for my $host ( keys %space ) {
    my @data;
    for ( split /\n/ , $space{$host} ) {
        next if /^host:volume/;
        my @field = $_ =~ /^([^:]+):([^\s]+)\s+(\d+)\s+(\d+)/;
        push @data, \@field;
    }
    for ( sort { $data[$a]->[2] <=> $data[$b]->[2] } 0 .. $#data ) {
        print join "\t" , @{ $data[$_] };
        print "\n";
    }
}