4**21 = 4,398,046,511,104. If each of those array elements took just 1 byte that would need 4000GB (or 4TB) of ram.

But each element of a Perl array requires a minimum of 32bytes on a 64-bit system, so that increases the programs memory requirement to at least 32,000GB.

And that's before you multiply by 197!

Even today, very few computers can access Terabytes of memory -- the latest greatest SkyLake will only address 128GB.

The bottom line is that you are going to have to tackle your problem a different way.

If you can describe what you are trying to do -- in computer terms, with a minimum of bio-lingo -- there is probably an approach that will allow you to achieve it without needing £432,000 worth of memory and a processor that can address it; if such an animal currently exists, it would be in the $millions price range.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority". The enemy of (IT) success is complexity.
In the absence of evidence, opinion is indistinguishable from prejudice. Suck that fhit

In reply to Re: Out of Memory when generating large matrix by BrowserUk
in thread Out of Memory when generating large matrix by cathyyihao

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