Tie::File does not work well on huge files. The following finds and prints the 20 millionth line of a 40 million line 3GB file in 12 seconds: 

c:\test>wc -l syssort
40000000 syssort

c:\test>dir syssort
19/12/2009  13:47     3,160,000,000 syssort

perl -le"$t=time;scalar<>for 1..20e6;print scalar<>;print time()-$t" s
+yssort
49_992_005_J1 chr9      97768833        97768867        ATTTTCTTCAATTA
+CATTTCCAATGCTATCCCAAA     +   35

12

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In reply to Re: Speed and memory issue with large files by BrowserUk
in thread Speed and memory issue with large files by firmament

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