> push @p, [ $p1, $p2];

I guess that creating 500e06 sub-arrays is the most memory consuming part.

I can't tell how efficient the usage of @d is, because it depends on how sparse the entries are used.

32 bits means 4.2e9 potential entries but with 500e6/256 = 1953125 in worst case you'll end up with 2200 empty entry ratio in @d. I bet a hash is more memory efficient then.

But it really depends what you are trying to achieve with all that data.

update

> which don't occur more than 256 times each.

your "test" doesn't reflect that.

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re: Memory efficient way to deal with really large arrays? by LanX
in thread Memory efficient way to deal with really large arrays? by sectokia

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