PGI User Forum
 SearchSearch   MemberlistMemberlist     RegisterRegister   ProfileProfile    Log inLog in 

CUDA-x86.

Launch failed error
Goto page Previous  1, 2
 
Post new topic   Reply to topic    PGI User Forum Forum Index -> Accelerator Programming
View previous topic :: View next topic  
Author Message
anirbanjana



Joined: 11 Aug 2012
Posts: 28

PostPosted: Tue Aug 06, 2013 8:27 am    Post subject: Reply with quote

Hi Mat and Alexey,
Thanks very much for all the inputs. I just flew back to Pittsburgh from Boston. I will follow up on each of your suggestions and post the results soon.

Best regards
Anirban
Back to top
View user's profile
anirbanjana



Joined: 11 Aug 2012
Posts: 28

PostPosted: Tue Aug 06, 2013 9:01 am    Post subject: Reply with quote

I tried the simplest suggestion first, which is to run the executable with cuda-memcheck, which returned 321 errors of the foll type at the crash point:
Code:

========= Invalid __global__ write of size 8
=========     at 0x00005a28 in calc_force_des_404_gpu
=========     by thread (191,0,0) in block (7,0,0)
=========     Address 0xb0273620c is misaligned
=========     Saved host backtrace up to driver entry point at kernel launch time
=========     Host Frame:/usr/lib64/libcuda.so (cuLaunchKernel + 0x3dc) [0xc9d5c]
=========     Host Frame:mfix.pgi13p3.exe [0x3a33e4]


Let me know if this provide any clue. I didn't have an AHA! moment seeing this. Could this possibly be caused by insufficient memory?

I am following up on the other suggestions.

Best regards
Anirban
Back to top
View user's profile
mkcolg



Joined: 30 Jun 2004
Posts: 6120
Location: The Portland Group Inc.

PostPosted: Tue Aug 06, 2013 9:41 am    Post subject: Reply with quote

Hi Anirban,

This error means that the program is writting to protected memory. You'll need to track down which line in this loop at line 404 of "calc_force_des" is causing the bad write.

- Mat
Back to top
View user's profile
anirbanjana



Joined: 11 Aug 2012
Posts: 28

PostPosted: Fri Sep 13, 2013 4:24 pm    Post subject: Reply with quote

I would just like to comment that by looking at the loop code line by line, I found that the issue was caused by a reduction variable that was not declared as such in the loop directive. After I declared
Code:

!$acc loop reduction(+: myvar)

the issue was resolved.


Thanks much for guiding me step by step through the debugging process.

Anirban
Back to top
View user's profile
Display posts from previous:   
Post new topic   Reply to topic    PGI User Forum Forum Index -> Accelerator Programming All times are GMT - 7 Hours
Goto page Previous  1, 2
Page 2 of 2

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © phpBB Group