I believe (not 100% sure though) that in your case (as you are putting one million keys into your hash and I assume you want to get them out again later) you should preallocate space by telling perl you need more buckets -i.e. 
my %hash;
keys(%hash)=1_000_000;

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The number you assign to keys is rounded up to the next power of two.

My understanding is (I would be interested to learn if this is correct) that when you have more buckets you have less collisions (i.e. entries that fall into the same bucket) and so retrieval of an entry is more efficient.

In reply to Re: Populating a hash by morgon
in thread Populating a hash by Anonymous Monk

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