Parallel Python(PP)平行計算測試
阿新 • • 發佈:2019-01-28
測試環境:i5-2300(4核) + Win7
使用PP的測試程式碼如下:
import math, sys, time import pp def takeuptime(n): chars = 'abcdefghijklmnopqrstuvwxyz0123456789' s = chars * 1000 for i in range(10*n): for c in chars: s.count(c) print """Usage: test.py [ncpus] [ncpus] - the number of workers to run in parallel, if omitted it will be set to the number of processors in the system """ # tuple of all parallel python servers to connect with ppservers = () #ppservers = ("10.0.0.1",) if len(sys.argv) > 1: ncpus = int(sys.argv[1]) # Creates jobserver with ncpus workers job_server = pp.Server(ncpus, ppservers=ppservers) else: # Creates jobserver with automatically detected number of workers job_server = pp.Server(ppservers=ppservers) print "Starting pp with", job_server.get_ncpus(), "workers" start_time = time.time() # The following submits 4 jobs inputs = (1000, 1000, 1000, 1000) jobs = [(input, job_server.submit(takeuptime, (input,), (), ())) for input in inputs] #wait for jobs in all groups to finish job_server.wait() print "Time elapsed: ", time.time() - start_time, "s" job_server.print_stats()
程式執行結果如下:
I:\Webscraping\test>test
Usage: test.py [ncpus]
[ncpus] - the number of workers to run in parallel,
if omitted it will be set to the number of processors in the system
Starting pp with 4 workers
Time elapsed: 20.9220001698 s
Job execution statistics:
job count | % of all jobs | job time sum | time per job | job server
4 | 100.00 | 78.6590 | 19.664750 | local
Time elapsed since server creation 20.9240000248
所需的時間和之前用pprocess模組進行並行運算的結果差不多。
PP與pprocess模組相比優勢在哪裡?
1)PP不但支援Linux,Windows下也能使用。
2)PP不但支援單機多核(SMP,systems with multiple processors or cores),而且支援多臺計算機(clusters,computers connected via network)。
目前只測試了SMP,期待clusters測試。