Python3用多线程替代for循环提升程序运行速度
[本文出自天外归云的博客园]
优化前后新老代码如下:
from git_tools.git_tool import get_collect_projects, QQNews_Git from threading import Thread, Lock import datetime base_url = "http://git.xx.com" project_members_commits_lang_info = {} lock = Lock() threads = [] ''' Author:zenkilan ''' def count_time(func): def took_up_time(*args, **kwargs): start_time = datetime.datetime.now() ret = func(*args, **kwargs) end_time = datetime.datetime.now() took_up_time = (end_time - start_time).total_seconds() print(f"{func.__name__} execution took up time:{took_up_time}") return ret return took_up_time def get_project_member_lang_code_lines(git, member, begin_date, end_date): global project_members_commits_lang_info global lock member_name = member["username"] r = git.get_user_info(member_name) if not r["id"]: return user_commits_lang_info = git.get_commits_user_lang_diff_between(r["id"], begin_date, end_date) if len(user_commits_lang_info) == 0: return lock.acquire() project_members_commits_lang_info.setdefault(git.project, dict()) project_members_commits_lang_info[git.project][member_name] = user_commits_lang_info lock.release() def get_project_lang_code_lines(project, begin_date, end_date): global threads git = QQNews_Git(project[1], base_url, project[0]) project_members = git.get_project_members() if len(project_members) == 0: return for member in project_members: thread = Thread(target=get_project_member_lang_code_lines, args=(git, member, begin_date, end_date)) threads.append(thread) thread.start() @count_time def get_projects_lang_code_lines(begin_date, end_date): """ 获取项目代码行语言相关统计——新方法(提升效率) 应用多线程替代for循环 并发访问共享外部资源 :return: """ global project_members_commits_lang_info global threads for project in get_collect_projects(): thread = Thread(target=get_project_lang_code_lines, args=(project, begin_date, end_date)) threads.append(thread) thread.start() @count_time def get_projects_lang_code_lines_old(begin_date, end_date): """ 获取项目代码行语言相关统计——老方法(耗时严重) 使用最基本的思路进行编程 双层for循环嵌套并且每层都包含耗时操作 :return: """ project_members_commits_lang_info = {} for project in get_collect_projects(): git = QQNews_Git(project[1], base_url, project[0]) project_members = git.get_project_members() user_commits_lang_info_dict = {} if len(project_members) == 0: continue for member in project_members: member_name = member["username"] r = git.get_user_info(member_name, debug=False) if not r["id"]: continue try: user_commits_lang_info = git.get_commits_user_lang_diff_between(r["id"], begin_date, end_date) if len(user_commits_lang_info) == 0: continue user_commits_lang_info_dict[member_name] = user_commits_lang_info project_members_commits_lang_info[git.project] = user_commits_lang_info_dict except: pass return project_members_commits_lang_info def test_results_equal(resultA, resultB): """ 测试方法 :param resultA: :param resultB: :return: """ print(resultA) print(resultB) assert len(str(resultA)) == len(str(resultB)) if __name__ == '__main__': from git_tools.config import begin_date, end_date get_projects_lang_code_lines(begin_date, end_date) for t in threads: t.join() old_result = get_projects_lang_code_lines_old(begin_date, end_date) test_results_equal(old_result, project_members_commits_lang_info)
老方法里外层for循环和内层for循环里均存在耗时操作:
1)git.get_project_members()
2)git.get_user_info(member_name, debug=False)
分两步来优化,先里后外或先外后里都行。用多线程替换for循环,并发共享外部资源,加锁避免写冲突。
测试结果通过,函数运行时间装饰器显示(单位秒):
get_projects_lang_code_lines execution took up time:1.85294
get_projects_lang_code_lines_old execution took up time:108.604177
速度提升了约58倍
本文来自博客园,作者:天外归云,转载请注明原文链接:https://www.cnblogs.com/LanTianYou/p/11498525.html