Here is what my code does:-

I have a file having 20+ millions of lines/records. ( say a.txt)

I have another file having around 600 lines/records (say b.txt) These lines have some categories. So, a category is matching to more than one line/records.

now; what my code does is:

1. Create a Hash out of b.txt ( key = category ; value=some mandatory part of the records ).

2. Read every record from a.txt and check if it matches with any of the mandatory part of the records ; if yes, create a file of that category and dump that entire line/record into that category.

So, every record (of 20+ millions) is getting compared with some (roughly saying) 600 odd records ( if we consider the match found would be the last record - in worst case )

And thats where the whole processing/looping is happening.

Please help. how can I expedite the process ?

In reply to Re^2: how to split huge file reading into multiple threads by sagarika
in thread how to split huge file reading into multiple threads by sagarika

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