Are you sure the slowdown is occurring at the filehandle close and not somewhere else in the program?

Do all those arrays need to remain in memory for the duration of the program?
Not knowing what your functions do makes it hard to offer suggestions.

Have you tried moving patch_stockfiles/delete_duplicates/fix_format/output inside the initial input loop and eliminating the array entirely?
Based on those subroutine names, it seems as if at least some of that can be done from inside the loop.
As is, it seems as if you're iterating over that huge array 4 separate times after creating it.

My suggestion would be to find a way to process this data piecewise (or in tandem), rather than as a whole. Is this possible?

In reply to Re: Perl Filehandle? by wojtyk
in thread Perl Filehandle? by Smersh2000

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