It sounds like you are running out of memory.

A 1_000_000 key hash with a reference to an empty hash as the value requires around 160 MB. For 8_000_000 keys, that would be 1.2 GB. Even with duplicates at each level, that is still a lot of hashes.

How much memory do you have in your machine? Have you monitored the memory consuption as the program runs?

Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"Think for yourself!" - Abigail
"Memory, processor, disk in that order on the hardware side. Algorithm, algoritm, algorithm on the code side." - tachyon

In reply to Re: puzzling seg fault by BrowserUk
in thread puzzling seg fault by ttown1079

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