The assumption that each cluster consists of exactly two servers is hardcoded into the last line.
#!/usr/bin/perl -T
use strict;
use diagnostics;

# --

sub get_cpu {
    my $servername    = shift;
    my %cpu    = (
        server1 => 10,
        server2 => 20,
        server3 => 5,
        server4 => 15,
    );
    return $cpu{$servername};
};

# --

my %servers    = (
    server1 => 'cluster1',
    server2 => 'cluster1',
    server3 => 'cluster2',
    server4 => 'cluster2',
);

my %clusters;
foreach my $servername (keys %servers) {
    $clusters{$servers{$servername}}    += get_cpu($servername);
};

print "$_:\t".($clusters{$_}/2)."\n" foreach sort keys %clusters;

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In reply to Re: clusters with hashes by Anonymous Monk
in thread clusters with hashes by Anonymous Monk

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