> . The output file has 1.7 trillion records

Sorry but the whole concept is questionable.

You are multiplying two files to effectively waste disc space with highly redundant information.

I'd rather consider putting those two sources in a DB (or something similar) and to join them on demand.

If the target consumer really needs files try faking them with a filesystem facade which interfaces the DB.

I wouldn't be surprised if this bridge was faster than accessing a huge static file on a hard disk.

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery FootballPerl is like chess, only without the dice

In reply to Re: Speed up file write taking weeks by LanX
in thread Speed up file write taking weeks by Sanjay

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