I have a program that reads and processes approximately 8 million lines of data. For each line read it does:

my @aa = split(/\t/); @{$ref}{@head} = @aa;

Well, sorry, but that program does seem to make any sense. As far as we can say from the code you presented, this program is just assigning 8 million times the split line to the same HoH element (nothing is ever changing $ref or @head). If this is what you want to do, then simply go to the last line of the file and assign its split value to your variable. But, of course, I suspect you want to to something else, but are not really saying what.

Please explain what you really want. Or, stated differently, please provide a more comprehensive excerpt of your code.

In reply to Re: Faster Hash Slices by Laurent_R
in thread Faster Hash Slices by jht

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