on my computer (for 1M elements): 
               s/iter      BrowserUK packed_default        SortKey
BrowserUK        71.7             --           -66%           -79%
packed_default   24.5           193%             --           -38%
SortKey          15.2           372%            61%             --

[download]
another important point for sorting algorithms is their memory comsumption, and the GRT offers the worst behaviour for that aspect: 
use Memchmark qw(cmpthese);

...

cmpthese(BrowserUK => \&BrowserUK,
     packed_default => \&packed_default,
     SortKey => \&SortKey );
__end__

test: BrowserUK, memory used: 102006784 bytes
test: SortKey, memory used: 85598208 bytes
test: packed_default, memory used: 182788096 bytes

[download]
(Memchmark results are approximate, but accurate enough to show the difference)

In reply to Re^4: Sorting a hash of arrays based on a particular array element. by salva
in thread Sorting a hash of arrays based on a particular array element. by aditya.singh

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