Using a standard hash and pack like so, it requires 1.12GB to store the 10e6 key/value pairs:

$h{ pack 'V', $uintKey } = pack 'H*', $32byteHexValue;

[download]

Workable on most modern systems. How much smaller are you looking for?

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
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In reply to Re^3: Store large hashes more efficiently by BrowserUk
in thread Store large hashes more efficiently by puterboy

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