Have you tried read()? If the records are fixed length you could read in for a length * number rows and then split on the newline or read in a big chunk and add logic to keep a partial record from the end of the buffer and add to it on the next read. 

   while ( read($fh, $buf, $len) ) {
       @lines = split "\n", $buf;
       .
       .
       .
   }

[download]
It may be faster, worth a try.

In reply to Re: Perl Read-Ahead I/O Buffering by sth
in thread Perl Read-Ahead I/O Buffering by jeffthewookiee

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