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Re: std::list.sort() blocks on very large lists (>12GB) GCC 4.0.1 Mac OS X 64-bit


jpitt@fhcrc.org wrote:
I'm experiencing a weird problem that makes me wonder if there is a problem with the std::list.sort member function when used on very large lists. I have a very large list (~20GB) that is made up of a class (382bytes each) of DNA sequence data. When the list is on the order of 12GB it sorts fine, but if it gets up into the 17GB range when I call sort() it seems to block. The list has already been built so I don't think it's a malloc issue. I also don't think it's a complexity problem because the 12GB list sorts fine (it takes a minute or so), so I'm wondering if the std sort method doesn't properly handle the excess memory available in 64bit mode? Has anyone experienced this?

Double check the comparison function you're using. If it doesn't properly conform to the specification, sort() can get into an infinite loop. Here's some info on the matter:


http://blogs.msdn.com/oldnewthing/archive/2009/05/08/9595334.aspx
http://blogs.msdn.com/oldnewthing/archive/2003/10/23/55408.aspx

Cheers,
Nicholas Sherlock


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