PGI User Forum

IrinaDDD · Joined: 24 Jan 2012 Posts: 12

Thank you, Mat.
You helped me a lot.

Best regards,
Irina

IrinaDDD · Joined: 24 Jan 2012 Posts: 12

Hi, Mat,

The results I showed you before with small data copies before each kernel was obtained, by using 12.5 version of the PGI compiler.
Now, when I use 12.10 version there are much less copies then it was for 12.5 one, but, for some reason, execution time for one of the kernels became about 3 times longer.
I specify grid and block size by myself, so, this parameters are fixed.
Execution time for other kernels doesn’t change and I wonder why only one of the kernels shows different results?

Thank you in advance,

Irina.

mkcolg · Posted: Mon Jan 28, 2013 12:26 pm Post subject:

Hi Irina,

We introduced OpenACC in 12.6 and with it some major changes.

I would consider your issue a performance bug, especially if you were able to work around it by explicitly setting the schedule. Scheduling is very difficult so when the compiler's automatic scheduler is getting it wrong, we'd like to know about it. Can you send a report to PGI Customer Service (trs@pgroup.com) and include a reproducing example?

Thanks,
Mat