The following low tech solution may or may not work for you -- it trades millions of seeks for several sequential rewrites of the file (similar to BrowserUks solution) and doesn't require much code at all.

Rewrite the files with a random number prepended or appended to each line. Run the new files through GNU sort but be sure to use the -T flag to send temp files to a place where you have some free disk preferrably on a different physical disk, (enough for about 1.5 - 2x the size of the largest file), you could send the output through a pipe where a process then removes the random number from each line.

NOTE: I recall being able to sort text files close to a GB with GNU sort, in reasonable time, but I'm not sure how it handles files much large than this.

In reply to Re: Strategy for randomizing large files via sysseek by bluto
in thread Strategy for randomizing large files via sysseek by Anonymous Monk

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