When writing a crawler, I want to save the crawled data into the database. There are many entries in each page. For example, a person may have many visitors, so I insert the unloading loop,

                try:
                    sql_visitor='INSERT INTO visitor (ownername,owneruid,visitorname,visitoruid,visittime) VALUE ("%s",%d,"%s",%d,"%s")'%(ownername,owneruid,visitorname,visitoruid,visitortime)
                    print sql_visitor
                    self.cursor.execute(sql_visitor)
                    self.connect.commit()
                except Exception as e:
                    print e

One page has one thread. If I dislike the slowness, I opened 5

max_threads=5
        while uid < 8000000 or threadlist:
            for thread1 in threadlist:
                if not thread1.is_alive():
                    threadlist.remove(thread1)
            while len(threadlist) < max_threads and uid < 8000000:
                uid+=1
                thread2=threading.Thread(target=run,args=(uid,))
                thread2.setDaemon(True)
                thread2.start()
                threadlist.append(thread2)
            time.sleep(5)

Run very smoothly:

INSERT INTO visitor (ownername,owneruid,visitorname,visitoruid,visittime) VALUE ("huosai7",4893,"Liang2017",7252799,"2017-5-22 21:06")
INSERT INTO personalinfo (ownername,owneruid,jifen,huajiao,xiaomijiao,jinbi,haoyou,zhuti,rizhi,xiangce,fenxiang,kongjianfangwenliang,youxiangyanzheng,shipinrenzheng,juzhudi,chushengdi,shangcifabiaoshijian,shangcihuodongshijian,zuihoufangwen,zhuceshijian,zaixianshijian,shengri,xingbie ) VALUE( "huosai7",4893,0,0,0,0,0,0,0,0,0,0,0,0,"","","2100-01-01 12:00","2100- 01-01 12:00","2100-01-01 12:00","2004-1-3 19:28",0,"2100-01-01 12:00",0)
INSERT INTO visitor (ownername,owneruid,visitorname,visitoruid,visittime) VALUE ("龙乐",4894,"Liang2017",7252799,"2017-5-22 21:06")
(1062, "Duplicate entry '4894- 7252799-2017-05-22 21:06:00' for key 'PRIMARY'")
INSERT INTO personalinfo (ownername,owneruid,jifen,huajiao,xiaomijiao,jinbi,haoyou,zhuti,rizhi,xiangce,fenxiang,kongjianfangwenliang ,youxiangyanzheng,shipinrenzheng,juzhudi,chushengdi,shangcifabiaoshijian,shangcihuodongshijian,zuihoufangwen,zhuceshijian,zaixianshijian,shengri,xingbie) VALUE("龙乐",4894,0,0,0,0,0,0,0,0,0, 0,0,0,"","","2100-01-01 12:00","2100-01-01 12:00","2100-01-01 12:00","2004-1- 3 20:21",0,"2100-01-01 12:00",0)
..........

So I set max_thread to 10, so the results are as follows:

INSERT INTO visitor (ownername,owneruid,visitorname,visitoruid,visittime) VALUE ("xiao61",4889,"Liang2017",7252799,"2017-5-22 21:06")

(2006, 'MySQL server has gone away')

INSERT INTO personalinfo (ownername,owneruid,jifen,huajiao,xiaomijiao,jinbi,haoyou,zhuti,rizhi,xiangce,fenxiang,kongjianfangwenliang,youxiangyanzheng,shipinrenzheng,juzhudi,chushengdi,shangcifabiaoshijian,shangcihuodongshijian,zuihoufangwen,zhuceshijian,zaixianshijian, shengri ,xingbie) VALUE("xiao61",4889,0,0,0,0,0,0,0,0,0,0,0,0,"","","2100-01-01 12:00 ","2100-01-01 12:00","2100-01-01 12:00","2004-1-3 15:56",0,"2100-01-01 12:00",0)

(2006, 'MySQL server has gone away')

INSERT INTO visitor (ownername,owneruid,visitorname,visitoruid,visittime) VALUE ("confused cool bear",4897,"Liang2017",7252799,"2017-5-22 21:06")

(2006, 'MySQL server has gone away')

INSERT INTO personalinfo (ownername,owneruid,jifen,huajiao,xiaomijiao,jinbi,haoyou,zhuti,rizhi,xiangce,fenxiang,kongjianfangwenliang,youxiangyanzheng,shipinrenzheng,juzhudi,chushengdi,shangcifabiaoshijian,shangcihuodongshijian,zuihoufangwen,zhuceshijian,zaixianshijian, shengri ,xingbie) VALUE("confused cool bear",4897,611,0,1655,0,0,2,0,0,0,34,0,0,"","","2007-3-27 00:37","2007-3-27 00:37","2007-3-27 00:37","2004-1-3 21:08",0,"2100-01-01 12:00" ,1)

(2006, 'MySQL server has gone away')
..........

It can be seen that 2006 came out, and then I set max_thread to 30, and the results are as follows:

That’s it, is it detailed enough? If it’s not detailed enough, what else do you need? Just tell me!