multiscan should probably check if there's enough memory to run the biggest tests

[GoogleCodeExporter]

512 MB GPU DRAM doesn't appear to be enough to run the biggest multiscan tests. 
Check to see if there's enough DRAM to run 'em.

Original issue reported on code.google.com by jow...@gmail.com on 12 Jul 2011 at 2:08

[GoogleCodeExporter]

Just doing math, on my Mac, this is failing here:

Running a sum-multiscan of 2097152 longlong elements in 10 rows
Cuda error in file 'test_scan.cpp' in line 430 : out of memory.

The malloc here will be 2M elements * 2 arrays (in/out) * 8B/element * 10 rows 
= 320 MB. 

The CUDA mallocs and frees in the testrig completely match up, so I'm not 
suspecting memory leaks. So I guess we have to conclude that 320 MB alloc is 
just too much for a 512 MB GPU, and we should check if we only have 512 MB and 
chop down the max if necessary.

Original comment by jow...@gmail.com on 12 Jul 2011 at 5:38

[GoogleCodeExporter]

I put in a rough calculation that we can refine if we still see failures.  
Please set status to verified if it passes on your macbook.

Original comment by harr...@gmail.com on 22 Jul 2011 at 7:00

• Changed state: Fixed

[GoogleCodeExporter]

{{{
% bin/cudpp_testrig -multiscan -iterations=1
}}}

passes on my laptop now. Woo!

Original comment by jow...@gmail.com on 22 Jul 2011 at 4:04

• Changed state: Verified