Use of GPU in TOPAS

tkosuge

Dear all,

I am currently attempting to perform sequential refinement of over 1000 diffraction patterns. I would like to speed up the calculations, is it possible to use GPU in TOPAS?
Also, I know it will depend on the environment, but if you know which would be more efficient to increase CPU and memory performance to speed up TOPAS calculations, please let me know.

I would appreciate your advice.

Kind regards,
Taiki

rowlesmr

Which version of TOPAS are you using? THere are significant speedups goin gfrom 5 to 6 to 7.

If you're doing sequential refinements, you probably aren't running into memory issues, so a faster CPU could help. v7 (and maybe 6?) is fully multithreaded, so more cores could also help.

For simultaneous refinements, memory is definitely a bottleneck. have a look at http://scripts.iucr.org/cgi-bin/paper?nb5289, particularly the SI.

Matthew

alan-coelho

TOPAS does not make if a GPU. I also dont think a GPU will help a program such as TOPAS. TOPAS uses threading and vectorization. Threading often leads to a 4 fold increase in speed for an 8 core CPI and vectorization a five fold increase in speed for simple loops where data access in memory is sequential. Version 7 can also use Amazon cloud computing, see http://www.topas-academic.net/Technical_Reference.pdf for details.

tkosuge

Dear Alan and Matthew,

In reference to your post, I have decided to buy a computer to run TOPAS, focusing on CPU and memory.
Thanks for your replies and your helpful advice!

Kind regards,
Taiki