Content deleted Content added
m Replaced 1 bare URLs by {{Cite web}} |
still was not very clear about control signals, especially given NVIDIA and AMD and ILLIAC IV all using different terminology Tags: Mobile edit Mobile web edit Advanced mobile edit |
||
Line 18:
[[Vector processor#Difference between SIMD and vector processors|difference between SIMD and vector processors]] is primarily the presence of a Cray-style {{code|SET VECTOR LENGTH}} instruction.
One key distinction between SIMT and SIMD is that the SIMD unit will not have its own memory (a SIMT system could ''use'' a SIMD unit as an array element: such an arrangement is usually termed [[SIMD lanes]]).
Another key distinction in SIMT is the presence of control flow mechanisms like warps ([[Nvidia]] terminology) or wavefronts (Advanced Micro Devices ([[AMD]]) terminology). [[ILLIAC IV]] simply called them "Control Signals". These
Each hardware element (PU, or PE in [[ILLIAC IV]] terminology) working on individual data item sometimes also referred to as a [[SIMD lane]] or channel, although the ILLIAC IV PE was a scalar 64-bit unit. Modern [[graphics processing unit]]s (GPUs) are invariably wide [[SIMD within a register]] (SWAR) and typically have more that 16 data lanes or channels of such Processing Elements.{{cn|date=July 2024}} Some newer GPUs integrate mixed-precision {{cn|date=July 2025}} SWAR pipelines, which performs concurrent sub-word [[8-bit computing|8-bit]], [[16-bit computing|16-bit]], and [[32-bit computing|32-bit]] operations. This is critical for applications like AI inference, where mixed precision boosts throughput.
| |||