What are null commands in mysql?

Question

Nginx

An HTTP request in django makes a fetch from the database.

mysql> SHOW PROCESSLIST;
+-------+-----------+------------------+-----------+---------+------+--------------+---------------------------------------------------------------------------------+
| Id    | User      | Host             | db        | Command | Time | State        | Info                                                                            |
+-------+-----------+------------------+-----------+---------+------+--------------+---------------------------------------------------------------------------------+
| 21011 | user_b520 | localhost        | NULL      | Query   |    0 | starting     | SHOW PROCESSLIST                                                                |
| 24363 | user_b520 | 172.19.0.9:35984 | dev_NT_pr | Query   |    0 | Sending data | SELECT COUNT(*) AS `__count` FROM `api_message` WHERE `api_message`.`error` = 1 |
| 24364 | user_b520 | 172.19.0.9:35990 | dev_NT_pr | Sleep   |    0 |              | NULL                                                                            |
| 24365 | user_b520 | 172.19.0.9:35992 | dev_NT_pr | Sleep   |    0 |              | NULL                                                                            |
| 24366 | user_b520 | 172.19.0.9:35994 | dev_NT_pr | Sleep   |    0 |              | NULL                                                                            |
| 24367 | user_b520 | 172.19.0.9:35996 | dev_NT_pr | Sleep   |    0 |              | NULL                                                                            |
| 24368 | user_b520 | 172.19.0.9:35998 | dev_NT_pr | Sleep   |    0 |              | NULL                                                                            |
+-------+-----------+------------------+-----------+---------+------+--------------+---------------------------------------------------------------------------------+
7 rows in set (0.00 sec)

What are these sleep queues with null information?
Decided to figure it out, because mysql uses 29% of the processor from one sample
According to the query schedule, it starts to stutter at 140 clients per second. mysql does 140 samples per second, is this too small an indicator?

Answer 1

https://nginx.org/ru/docs/http/ngx_http_rewrite_mo...

Answer 2

hangs a connection, does nothing, waits for a timeout to fall off