What is Prefix sum?

Computing the running totals of an array from the start, also called a scan. It can be computed in parallel and is used to find write positions when compacting output.

Field: GPU Programming

Prefix sum in the explanations

Representing whether each thread outputs as 0 or 1 and computing the running total from the start (an exclusive prefix sum) gives each thread "the number of outputting threads before me", which is exactly its write address.
On a GPU you want to compact only the elements meeting a co…

Questions that mention Prefix sum (1)

On a GPU you want to compact only the elements meeting a condition into another array (each thread outputs 0 or 1 items). Which parallel computation is commonly used to determine each thread's write position?

Related terms

GPU Bank conflict Constant memory CUDA GPU kernel GPU occupancy GPU shared memory Grid-stride loop Latency hiding Memory coalescing

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