SIMT Instruction Scalarization for Redundant Thread Execution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing single instruction multiple thread (SIMT) processing architectures face inefficiencies due to redundant execution of deterministic instructions across multiple threads, leading to increased power consumption and resource utilization, particularly for operations that are expensive in terms of silicon use and execution time.
Innovation Solution
Adapting the SIMT execution model to utilize a serial execution unit for executing certain operations, where multiple threads execute the same deterministic instruction using a serial execution unit, with the result being shared among all threads, and employing a scalarization process involving peeling loops to partition and unwind thread execution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple threads execute the same deterministic instruction in parallel using SIMT architecture, then processing throughput is improved, but power consumption and resource utilization increase due to redundant execution
Solution Approach 1:
The patent segments thread execution into two categories: deterministic instructions that can be executed in parallel across multiple threads, and non-deterministic instructions that require serial execution. This segmentation allows the system to optimize power consumption by avoiding redundant execution of non-deterministic instructions while maintaining high throughput for deterministic operations.
Solution Approach 2:
The patent introduces dynamic execution mode selection where the system can switch between parallel SIMT mode for deterministic instructions and serial execution mode for non-deterministic instructions. This dynamic adaptation allows optimal resource utilization by selecting the execution mode that minimizes power consumption and redundancy for each specific instruction type.
2Productivity
If multiple threads execute the same deterministic instruction in parallel using SIMT architecture, then processing throughput is improved, but resource utilization and silicon use increase
Solution Approach 1:
The patent segments instruction execution into parallel and serial paths based on determinism. By identifying which instructions are deterministic and which are not, the system can allocate resources efficiently, avoiding the need to provision full parallel execution paths for all instructions, thereby reducing overall device complexity and silicon area.
Solution Approach 2:
The patent implements a universal execution model where a single execution unit can handle both parallel and serial execution modes. This multi-functionality allows the same hardware resources to serve multiple purposes, reducing the need for separate dedicated resources for different execution modes and optimizing overall resource utilization.
3Use of energy by moving object
If serial execution unit is used for deterministic instructions, then power consumption is reduced by eliminating redundant computations, but execution time may increase
Solution Approach 1:
The patent implements dynamic mode selection where the execution unit can switch between serial and parallel execution based on the instruction type. For deterministic instructions, parallel execution is used to minimize time loss, while serial execution is used for non-deterministic instructions to save power, achieving optimal balance between speed and energy efficiency.
Solution Approach 2:
The patent changes the execution parameter from fixed parallel mode to variable mode based on instruction determinism. By detecting whether an instruction is deterministic or not, the system adjusts the execution parameter (serial vs. parallel mode) to optimize the trade-off between power consumption and execution time for each specific instruction.
Data Source
AI summary
Apparatuses, systems, and techniques to adapt instructions in a SIMT architecture for execution on serial execution units. In at least one embodiment, a predicate mask is initialized to identify a group of active threads associated with an instruction. The predicate mask is initialized with an inherited predicate of the instruction. The instruction is executed for a set of one or more threads selected from the group of active threads using a serial execution unit.