commit	ad0ca6ade44155d342d2480c579c143751d5891c	[log] [tgz]
author	Marat Dukhan <maratek@gmail.com>	Fri Oct 16 03:15:19 2015 -0400
committer	Marat Dukhan <maratek@gmail.com>	Fri Oct 16 03:15:19 2015 -0400
tree	1feb45b5106095217d7abe95c7f30c8c7efc104a
parent	90a03e7a4c9c48874dcb4bdefd0728f39524025f [diff]

tree: 1feb45b5106095217d7abe95c7f30c8c7efc104a

README.md

pthreadpool

pthreadpool is a pthread-based thread pool implementation. Is is intended to provide functionality of #pragma omp parallel for for POSIX systems where OpenMP is not available.

Features:

C interface (C++-compatible).
Run on user-specified or auto-detected number of threads.
Work-stealing scheduling for efficient work balancing.
Can be used in Portable Native Client and Native Client environment.
Extensive unit tests based on Google Test.

Example

The following example demonstates using the thread pool for parallel addition of two arrays:

static void add_arrays(struct array_addition_context* context, size_t i) {
  context->sum[i] = context->augend[i] + context->addend[i];
}

#define ARRAY_SIZE 4

int main() {
  double augend[ARRAY_SIZE] = { 1.0, 2.0, 4.0, -5.0 };
  double addend[ARRAY_SIZE] = { 0.25, -1.75, 0.0, 0.5 };
  double sum[ARRAY_SIZE];

  pthreadpool_t threadpool = pthreadpool_create(0);
  assert(threadpool != NULL);

  const size_t threads_count = pthreadpool_get_threads_count(threadpool);
  printf("Created thread pool with %zu threads\n", threads_count);

  struct array_addition_context context = { augend, addend, sum };
  pthreadpool_compute_1d(threadpool,
    (pthreadpool_function_1d_t) add_arrays,
    (void**) &context,
    ARRAY_SIZE);

  pthreadpool_destroy(threadpool);
  threadpool = NULL;

  printf("%8s\t%.2lf\t%.2lf\t%.2lf\t%.2lf\n", "Augend",
    augend[0], augend[1], augend[2], augend[3]);
  printf("%8s\t%.2lf\t%.2lf\t%.2lf\t%.2lf\n", "Addend",
    addend[0], addend[1], addend[2], addend[3]);
  printf("%8s\t%.2lf\t%.2lf\t%.2lf\t%.2lf\n", "Sum",
    sum[0], sum[1], sum[2], sum[3]);

  return 0;
}