JanS

Different Results on multiple Runs, only the last few Bits differ

Discussion created by JanS on Sep 15, 2010
Latest reply on Oct 15, 2010 by himanshu.gautam

Hi,

my program varies between 2 different results everytime i start it. It got different results on GPU & CPU either!

I'm using 10.7b, Windows 7 64bit and SDK 2.2. The problem existed on 2.1 too.

The result is computed out of an array of 175 unsigned longs, which seem to differ only at the last few bits.

Both results are CPU only. It doesn't matter how often i start it, it varies between these two results:

Starting kernel...

 

[0] 4283270082281354098

 

vs

[0] 4283270082281382770

 

[1] 10912951361200691065

vs

[1] 10912951361200006513

 

[2] 10790209076973444528

vs

[2] 10790209076973450672

 

[3] 2593268536612269050

vs

[3] 2593268536611711474

 

[4] 16457265885716341828

vs

[4] 16457265885716216900

 

 

Whats happening here? Do i got an Error in my program?

Maybe its because of the floating point accuracy?

The complete source code, kernel and .exe is here:

http://www.jevermeister.de/not_working.zip

If you want to use your CPU, just start it with an random command line argument. 

 

Thanks!

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