I'm currently writing scripts to read pipe-separated values from a very large text file (160+ GB). It's necessary to process every line, but this approach: @lines = <BIGGUNFILE> is unfeasible due to memory requirements. Currently the scripts use standard line by line behavior: while(my $line = <BIGGUNFILE>) I assume that this is pretty inefficient since it should cause a lot of very small reads instead of reading the data in large chunks. I've also experimented with Tie::File, which reports that it will buffer data, but this too seems to be line by line. I only need to process each line once, so buffering this way doesn't help me much. Is there another approach in Perl wherein I can read in larger chunks of data at a time, but yet not slurp in the whole file? In other words, I'd like to read-ahead and buffer a set of X lines so that the IO would be faster...

In reply to Perl Read-Ahead I/O Buffering by jeffthewookiee

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