Ensure GraphChi works with over 2B, or over 4B vertices

[GoogleCodeExporter]

In some cases we assume that vertex-ids can be converted to 32-bit signed 
integers. At least in the sliding-shards jump-index.

Fix and test with 4B vertices!

Original issue reported on code.google.com by akyrola...@gmail.com on 2 Jul 2012 at 2:59

[GoogleCodeExporter]

Hi all,

Where are we about this point?

I have got a graph with over 6B vertices. I changed vid_t from uint32 to 
uint64, did some minor changes in move_close_to() method, but still have a core 
dump during execution, not investigated yet.

Did others try?

Cheers

Original comment by gregory....@gmail.com on 7 Mar 2013 at 10:50

[GoogleCodeExporter]

Hi, this has not been worked on yet. I'll take a look soonish.

Original comment by akyrola...@gmail.com on 7 Mar 2013 at 1:35

[GoogleCodeExporter]

Hi Aapo,

seems to be OK now! By changing only move_close_to() and exec_updates() 
(replacing in the code some "int" with vid_t, which is now uint64_t for me), no 
more core dumped :-)

However, intervals are not what I expected, but doesn't seem very hard to fix 
:-)

Original comment by gregory....@gmail.com on 7 Mar 2013 at 4:30

[GoogleCodeExporter]

Excellent! Remember also to change all "atoi" to "atol" in preprocessing.hpp

Original comment by akyrola...@gmail.com on 7 Mar 2013 at 5:46