> Now in C, to do this I only need 5GB of ram: For the pairs: 500M * 4 (32bit int) * 2 (pairs) = 4GB. For the occurances: 1G * 1 (8bit int) = 1GB

that's an illusion, if you use an array of bytes in C, you'll have 2**32 potential points. That's already 4.3GB for the occurrence counts in @d, not 1GB.

But if you think it's that easy in C, you'll easily reproduce it's arrays with pack , substr and unpack in Perl.

Of course slower, but you haven't told us yet what your goal is.

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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