Question

我是python和Parallel Python的新手。问题是我要完成4个工作：生成4个掩码，将它们与输入图像相乘，然后进行进一步处理。以下是为并行处理而编写的代码片段。

inputs = range(4)
jobs = [(inpt, job_server.submit(PP, (inpt,input_data,size,(imageMultiply,blockCounter,imageQuantizer ), ("numpy","Image"))) for inpt in inputs]
job_server.print_stats()
for inpt, job in jobs:
  print "No of blocks in ", inpt, "is", job() ## accessing the result of pp

我得到的输出是：

Starting pp with 4 workers
Job execution statistics:
 job count | % of all jobs | job time sum | time per job | job server
         4 |        100.00 |       0.0000 |     0.000000 | local
Time elapsed since server creation 0.0219678878784
4 active tasks, 4 cores

No of blocks in  0 is 52
No of blocks in  1 is 61
No of blocks in  2 is 104
No of blocks in  3 is 48

我无法理解如果它不能同时处理，我仍然可以获得所需的输出，但所用的时间太长，这就是我想使用pp的原因。请帮我这个，这样我就可以成功减少时间。提前谢谢......

Answer 1

从print_stats()输出（此处重新格式化）

Job execution statistics:
 job count | % of all jobs | job time sum | time per job | job server
         4 |        100.00 |      16.0401 |     4.010028 | local
Time elapsed since server creation 4.04183793068
0 active tasks, 4 cores

一切似乎都很好。你有4个CPU核心;您可以在创建作业服务器后的4秒内完成4个作业;系统总共消耗了16个CPU秒来完成所有工作。

您可能需要尝试top -H，htop或Windows Sysinternals Process Monitor来实时观察CPU消耗。

并行Python不会出错，但并不会发生并行处理

1 个答案: