|Don't ask to ask, just ask|
Why when I store my 5 gb of file which has about 7m records of two columns, and I make two hashesh from two different files in the same format and size, even with a large ram (50gb) I run out of memory?
Assuming that your OS and Perl allow you full access to the full 50GB, you should not be running out of memory.
On a 64-bit system, a HoAs with 7 million keys and an average of 10 numbers per array requires ~3.5 GB. For two, reckon on 10 GB max.
I'm not aware of any restrictions or limits on the memory a 64-bit Perl can address, which leave you OS. Linux can apply per-process (and per-user?) limits to memory and cpu usage. I don't know what the commands are for discovering this information, but meybe that is somewhere you should be looking.
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