Glossary of rocPRIM terms

Glossary of rocPRIM terms#

This glossary is to help users understand the basic concepts or terminologies used in the rocPRIM library.

Block#: See tile. rocPRIM uses “block” and “tile” interchangeably.
Flat ID#: The flattened block or thread idex. The flat ID is a one-dimensional index created from two-dimensional or three-dimensional indices. For example the flat ID of a two-dimensional thread ID {X, Y} in a two-dimensional 128x4 block is Y*128*X.
Grid#: A group of blocks that all run the same kernel call.
Hardware warp size#: The number of threads in a warp as defined by the hardware. On AMD GPUs, the warp size can be either thirty-two (32) or sixty-four (64) threads.
Lane ID#: The identifier of the thread within the warp.
Logical warp size#: The number of threads in a warp as defined by the user. This can be equal to or less than the size of the hardware warp size.
SIMT#: See Single-Instruction, Multi-Thread.
Single-Instruction, Multi-Thread#: Single-instruction, multi-thread (SIMT) is a parallel computing model where all the work-items within a wavefront run the same instruction on different data.
Stride#: The number of threads per block.
Thread#: See work-item. rocPrim uses “thread” and “work-item” interchangeably.
Thread ID#: The identifier of the thread within a block.
Tile#: A group of warps that run on the same streaming multiprocessor (SM). Threads in the block can be indexed using one dimension, {X}, two dimensions, {X, Y}, or three dimensions, {X, Y, Z}. In rocPRIM the tile size is always the same as the block size.
Warp#: Alternate term for a wavefront. rocPRIM uses “warp”, “wave”, and “wavefront” interchangeably.
Warp ID#: The identifier of the warp within a block. A warp’s warp ID is guaranteed to be unique.
Wave#: See wavefront. rocPRIM uses “warp”, “wave”, and “wavefront” interchangeably.
Wavefront#: A group of threads that runs using the single instruction, multiple thread (SIMT) model.
Work-item#: A work-item is the smallest unit of parallel execution. A work-item runs a single independent instruction stream on a single data element.