Kokkos

Definition

Kokkos is a C++ library designed for performance portability, enabling developers to write code that can run efficiently on various hardware architectures, including CPUs and GPUs. This library simplifies the process of developing high-performance applications by providing abstractions for parallel execution and memory management, making it particularly relevant in exascale computing environments, resilient programming models, and performance portability across diverse architectures.

5 Must Know Facts For Your Next Test

1. Kokkos allows developers to write code once and run it on different platforms without major modifications, enhancing code maintainability.
2. The library supports a wide range of parallel execution models, such as threads and SIMD (Single Instruction Multiple Data), enabling developers to choose the best model for their specific application needs.
3. Kokkos abstracts memory management across different hardware architectures, making it easier to optimize data locality and minimize memory transfer times.
4. The library includes performance tuning features that help developers identify bottlenecks and optimize code for better performance on target hardware.
5. Kokkos is often used in conjunction with other libraries and frameworks, enhancing its capability to contribute to resilient programming models suitable for exascale computing.

Review Questions

• How does Kokkos facilitate performance portability in programming environments?
  • Kokkos promotes performance portability by allowing developers to write code that can be compiled and executed on various hardware architectures without significant changes. It achieves this through abstractions for parallel execution and memory management. This means that whether the target is a CPU or GPU, Kokkos can optimize the performance based on the architecture while keeping the codebase consistent, which is especially important in high-performance computing applications.
• In what ways does Kokkos contribute to resilient programming models in exascale computing?
  • Kokkos enhances resilient programming models by providing mechanisms that allow applications to recover from faults while maintaining performance. Its abstraction of hardware details means that even if a specific hardware component fails or underperforms, Kokkos can adapt the execution strategy without requiring extensive rework from the developer. This capability is vital for exascale systems where reliability is critical due to the scale and complexity of computations.
• Evaluate how Kokkos compares with other programming frameworks in terms of performance portability across architectures.
  • When compared to other frameworks like CUDA or OpenMP, Kokkos stands out due to its ability to provide a unified interface for diverse hardware platforms. While CUDA is specific to NVIDIA GPUs and OpenMP focuses primarily on shared-memory systems, Kokkos enables seamless integration of both CPU and GPU capabilities within a single codebase. This not only simplifies the development process but also maximizes resource utilization across different architectures. The result is improved performance portability that is essential for developing applications meant for exascale computing environments.

Related terms

CUDA: A parallel computing platform and application programming interface (API) model created by NVIDIA, allowing developers to use a C-like language to code algorithms for execution on GPUs.

OpenMP: An API that supports multi-platform shared-memory multiprocessing programming in C, C++, and Fortran, providing a set of compiler directives, library routines, and environment variables.

Thrust: A C++ template library for CUDA that provides a high-level interface for GPU programming, enabling efficient operations on data stored in device memory.