Release 4.1.0 (Master)

Table of Contents

• Release Summary
• Download
• System Requirements
• New Features
  • Taskflow Core
  • Utilities
• Bug Fixes
• Breaking Changes
• Documentation
• Miscellaneous Items

Taskflow 4.1.0 is the newest developing line to new features and improvements are actively introduced and supported. It is also where this documentation is generated. Many features are experimental and may change. While we strive for backward compatibility, breaking changes may occur when necessary to improve performance or simplify the software architecture.

Release Summary

Download

To download the newest version of Taskflow, please clone the master branch from Taskflow's GitHub.

System Requirements

To use Taskflow v4.1.0, you need a compiler that supports C++20:

• GNU C++ Compiler at least v11.0 with -std=c++20
• Clang C++ Compiler at least v12.0 with -std=c++20
• Microsoft Visual Studio at least v19.29 (VS 2019) with /std:c++20
• Apple Clang (Xcode) at least v13.0 with -std=c++20
• NVIDIA CUDA Toolkit and Compiler (nvcc) at least v12.0 with host compiler supporting C++20
• Intel oneAPI DPC++ Compiler at least v2022.0 with -std=c++20

Note

If your project does not support C++20, please use Taskflow v3.11.0, which can be downloaded here.

New Features

Taskflow Core

• added bulk cache update method in executor
• added more unit tests to test_notifiers.cpp
• added module support under taskflow/modules/
• added adopted module task to support composable tasking with move semantics
  • tf::Taskflow::adopt
  • tf::Task::adopt
• added the parallel-for algorithm over a multi-dimensional index range
  • tf::Taskflow::for_each_by_index (see Parallel Iterations)
• improved the dump format with proper indention
• improved the dump format of tf::Subflow with cluster-level edges
• optimized executor member variable data layout to reduce false sharing
  • aligned num_topologies to a cache line
  • aligned notifier to a cache line
• optimized tf::Executor::run(Taskflow&&) with asynchronous tasking
  • removed satellite field from both taskflow and executor classes
• optimized the locking cost of topology
• refactored the codebase with C++20 concept to enhance readability
  • credit goest to the amazing Anthropic Claude
• introduced a new profiler to replace the existing tfprof

Utilities

• added tf::HasGraph concept to check if a type has a tf::Graph
• added tf::StaticTask concept to check if a type is a static task
• added tf::SubflowTask concept to check if a type is a subflow task
• added tf::RuntimeTask concept to check if a type is a runtime task
• added tf::ConditionTask concept to check if a type is a condition task
• added tf::MultiConditionTask concept to check if a type is a multi-condition task
• added tf::Partitioner concept to check if a type is a partitioner
• added tf::IndexRangeLike concept to define N-dimensional index ranges
• added tf::IndexRange to perform parallel iterations over an N-dimensional range
• removed floor_log2 due to duplication with C++20 std::bit_width
• removed cpu_pause due to platform-dependent implementation

Bug Fixes

• fixed the scope bug in creating tf::Future<T> from std::future (#761)
• fixed the async bug in taking name as a parameter
• fixed the redundant call when N is zero in for_each_by_index

Breaking Changes

• renamed tf::IndexRange::discrete_domain to tf::IndexRange::unravel

Documentation

• switched to the native doxygen for C++20 support
• revised Cookbook
  • added video tutorial links
• revised Composable Tasking
  • added Create an Adopted Module Task
• revised Profile Taskflow Programs
• revised Parallel Iterations
  • added Create an IndexRange-based Parallel-Iteration Task
• revised Learning from Examples
  • added 3D Stencil Computation
  • added Divide-and-Conquer Parallelism
  • added Async Producer-Consumer Pipeline
  • added Dynamic Dependency Graph
  • added Parallel Breadth-First Search
  • added Blocked Cholesky Factorization
  • added Sparse Matrix-Vector Multiplication
  • added 2D Image Convolution
  • added Travelling Salesman Problem
  • added Graph Coloring
  • added Critical Path Scheduling
  • added Incremental Build Graph
  • added Speculative Execution
• revised Profile Taskflow Programs

Miscellaneous Items

If you are interested in collaborating with us on applying Taskflow to your projects, please feel free to reach out to Dr. Tsung-Wei Huang!