mysql - Django mysql 连接太多

Question

我用的是Django和mysql，遇到连接太多的问题。

我从命令行运行 python 脚本，但与 Django 模型集成以检查数据库中的数据。该脚本每 30 秒运行一次，我使用线程来控制它。 My_function 是将检查数据库状态的函数。

while True: 
    now = time.time() 
    if now < next: 
        time.sleep(next - now) 
        t = Thread(target=my_function,)
        t.start()# start a thread

    next += interval

问题出在我监控mysql服务器的时候。一直有大约10个连接，它们都在休眠。我只是不明白为什么。有 2 个事件的 python 线程不断运行，所有其他线程在完成时终止。为什么mysql连接数是10？任何人都可以帮助我吗？非常感谢!

更新 1:现在放上mysql processlist的截图。连接都处于 sleep 模式并且什么都不做，创建连接的线程已经终止。这真的很奇怪。

+------+------+-----------------+----------+---------+-------+-------+------------------+
| Id   | User | Host            | db       | Command | Time  | State | Info             |
+------+------+-----------------+----------+---------+-------+-------+------------------+
|  411 | root | localhost:47347 | NULL     | Sleep   |     2 |       | NULL             |
|  412 | root | localhost:47350 | NULL     | Sleep   |     3 |       | NULL             |
|  479 | root | localhost       | NULL     | Sleep   | 27164 |       | NULL             |
|  918 | root | localhost       | EZ_Green | Sleep   | 14006 |       | NULL             |
|  953 | root | localhost       | EZ_Green | Sleep   | 12956 |       | NULL             |
|  989 | root | localhost       | EZ_Green | Sleep   | 11874 |       | NULL             |
| 1025 | root | localhost       | EZ_Green | Sleep   | 10796 |       | NULL             |
| 1061 | root | localhost       | EZ_Green | Sleep   |  9716 |       | NULL             |
| 1097 | root | localhost       | EZ_Green | Sleep   |  8636 |       | NULL             |
| 1132 | root | localhost       | EZ_Green | Sleep   |  7586 |       | NULL             |
| 1168 | root | localhost       | EZ_Green | Sleep   |  6506 |       | NULL             |
| 1204 | root | localhost       | EZ_Green | Sleep   |  5426 |       | NULL             |
| 1240 | root | localhost       | EZ_Green | Sleep   |  4346 |       | NULL             |
| 1276 | root | localhost       | EZ_Green | Sleep   |  3266 |       | NULL             |
| 1312 | root | localhost       | EZ_Green | Sleep   |  2186 |       | NULL             |
| 1348 | root | localhost       | EZ_Green | Sleep   |  1106 |       | NULL             |
| 1384 | root | localhost       | EZ_Green | Sleep   |    26 |       | NULL             |
| 1385 | root | localhost       | NULL     | Query   |     0 | NULL  | show processlist |
+------+------+-----------------+----------+---------+-------+-------+------------------+

Answer 1

正如尘土飞扬所说，

Every thread that uses Django ORM creates a new database connection. And Django will not manage the connection automatically that created by your own thread. So you should manage it.

您可以在每个线程退出之前简单地执行此操作:

from django.db import connection

# your work thread method 

def my_function():
    # do something...
    # close the db connection explicitly

    connection.close()