Well (d'oh), an important thing I forgot to mention is that I also need to know where I am in the $HoH for any given value. So I not only need to find the top x (10 in my case) values of $HoH->{$foo}{$bar}, but I also need to keep track of the value of $foo and $bar for each of those x values.

Anyway, your code gave me some idea and this is what I've come up with for now. 
while (my $kid_ = $kills_sth->fetchrow_hashref()){
    $KP->{$kid_->{k}}{$kid_->{v}}++;
}
# How many do we keep?
my $total = 10;
my %top;

for(keys %{$KP}){
    # Player ID
    my $pid = $_;
    VAL:
    for ( keys %{$KP->{$pid}}) {
        # Target ID
        my $tid = $_;
        my $frags  = $KP->{$pid}{$tid};
        for(0 .. ($total - 1)){
            my $idx = $_;
            $top{$idx}{f} ||= 0;
            if(($idx != ($total - 1)) && $frags > $top{$idx}{f}){
                my $idx2 = $idx + 1;
                $top{$idx2}{k}   = $top{$idx}{k};
                $top{$idx2}{v}   = $top{$idx}{v};
                $top{$idx2}{f}   = $top{$idx}{f};
                $top{$idx}{k}    = $pid;
                $top{$idx}{v}    = $tid; 
                $top{$idx}{f}    = $frags; 
                next VAL;
            }
            elsif(($idx == ($total - 1)) && ($frags > $top{$idx}{f})){
                $top{$idx}{k} = $pid;
                $top{$idx}{v} = $tid;
                $top{$idx}{f} = $frags;
                next VAL;
            }
        }
    }
}

for(0 .. ($total - 1)){
    my $id = $_;
    printf("%2s. p: %s\tt: %s\tf: %s\n",($id+1),$top{$id}{k},$top{$id}
+{v},$top{$id}{f});
}

[download]
Still, it seems awfully inefficient to me and I'm really leary of it's ninja scaling abilities. But that said, it works and produces the intended results: 
 1. p: 2838413  t: 3440380      f: 328
 2. p: 2838413  t: 1261188      f: 282
 3. p: 539960   t: 2976790      f: 273
 4. p: 3440380  t: 2838413      f: 268
 5. p: 182560   t: 53957        f: 206
 6. p: 539960   t: 53957        f: 196
 7. p: 1261188  t: 53957        f: 190
 8. p: 539960   t: 3440380      f: 171
 9. p: 3440380  t: 539960       f: 146
10. p: 53957    t: 1261188      f: 127

[download]

I'd appreciate any ideas about increasing efficiency.

Thanks a bunch for your help.

ps. Yes, it's a half-life stats program. :)

In reply to Re: Re: Re: Sorting values of nested hash refs by doran
in thread Sorting values of nested hash refs by doran

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