使用python进行子进程管理

Question

我有一个数据分析脚本,它接受一个参数,指定要执行的分析段.我想在'n'是机器上的核心数的时候运行脚本的'n'个实例.复杂的是,分析的部分比核心要多,所以我想最多运行,"n"个进程,其中一个完成,再启动另一个.在使用子进程模块之前,有没有人做过这样的事情？

Answer 1

我认为多处理模块将帮助您实现所需.看看示例技术.

import multiprocessing

def do_calculation(data):
    """
    @note: you can define your calculation code
    """
    return data * 2

def start_process():
    print 'Starting', multiprocessing.current_process().name

if __name__ == '__main__':
    analsys_jobs = list(range(10))  # could be your analysis work
    print 'analsys_jobs :', analsys_jobs

    pool_size = multiprocessing.cpu_count() * 2
    pool = multiprocessing.Pool(processes=pool_size,
                                initializer=start_process,
                                maxtasksperchild=2, ) 
    #maxtasksperchild = tells the pool to restart a worker process \
    # after it has finished a few tasks. This can be used to avoid \ 
    # having long-running workers consume ever more system resources

    pool_outputs = pool.map(do_calculation, analsys_jobs)   
    #The result of the map() method is functionally equivalent to the \
    # built-in map(), except that individual tasks run in parallel. \
    # Since the pool is processing its inputs in parallel, close() and join()\
    # can be used to synchronize the main process with the \
    # task processes to ensure proper cleanup.  

    pool.close() # no more tasks
    pool.join() # wrap up current tasks


    print 'Pool :', pool_outputs

你可以找到很好的在这里多技术入手