This maybe caused by memory access collisions and/or lack of coalesced
memory access. This technical report gives some pointers:
Do you use atomic operations? Or maybe you have too many thread fences?
I have no problem starting many threads: the number of threads alone is
not the issues.
Op 6-6-2018 om 8:37 schreef aseem hegshetye:
Does GPU speed exponentially drop as number of threads increase beyond
a certain number?. I used to allocate number of threads= number of
transactions in data under consideration.
For Tesla K80 I see exponential drop in speed above 30290 Threads.
If true, is it a best practice to keep number of threads low and
iterate over the data to get results at optimum speed.
How to find best number of threads for a GPU?
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