I need to sort huge binary files that won’t fit into memory. It’s no option to use a sort algorithm and continuously read/write from I/O device. Is there any possibility to use something like a memory mapped file?
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I need to sort huge binary files that won’t fit into memory. It’s no option to use a sort algorithm and continuously read/write from I/O device. Is there any possibility to use something like a memory mapped file?
This is a solved problem, as explained on this wiki page: http://en.wikipedia.org/wiki/External_sorting
Basically, read in some set amount, sort it, save into a file, and repeat.
Then, read in a smaller amount from each file, sort these, and continue until done.
UPDATE:
You may want to look at the java code he uses, it sounds like he solved what you need.
http://www.codeodor.com/index.cfm/2007/5/10/Sorting-really-BIG-files/1194