Hi Cristoforo. I'm trying it anyway :) I appreciate your help! Will look at Eily's solution, too.

[root@WarGame2 BRRX]# time ./a.pl
26662441 xre hash size -- 26662441 xre hash keys
14700586 rdk hash size -- 14700586 rdk hash keys
23405918 bid hash size -- 23405918 bid hash keys
doing the set scalar stuff
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