按照先查看日志再排查的原理，先去看vim /usr/local/php/etc/php-fpm.conf，看到日志文件是在：error_log = /usr/local/php/var/log/php-fpm.log
日志中报了如下：
WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 8 children, there are 0 idle, and 100 total children
WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 32 children, there are 0 idle, and 1591 total children
WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 8 children, there are 27 idle, and 3511 total children
[root@120-24-111-219 log]# vim /usr/local/php/etc/php-fpm.conf
pm = dynamic
pm.max_children = 5800
pm.start_servers = 800
pm.min_spare_servers = 40
pm.max_spare_servers = 5800
参数分析： pm= dynamic 表示php启用的动态模式 注： php有动态和静态(static)两种工作模式，默认是动态模式。 pm.max_children 表示静态下最大线程数 pm.start_servers 表示动态下启动时的线程数，该参数大于pm.min_spare_servers，小于pm.max_spare_servers pm.min_spare_servers 表示动态下最小空闲线程数 pm.max_spare_servers 表示动态下最大空闲线程数 工作模式： Static模式 当工作模式设置为静态后，就只有pm.max_children项有效，即表示php-fpm工作时一直保持的线程数。 Dynamic 模式 动态模式下，与他相关的参数有pm.start_servers、pm.min_spare_servers 、pm.max_spare_servers，分别表示开启的php进程数，最小的进程数、与最大的进程数。 模式比较： 静态模式的话，比较适合一些内存比较大一点的服务器，8G及以上的，因为对于比较大内存的服务器来说，设置为静态的话会提高效率。 动态模式适合小内存机器，灵活分配进程，省内存。可以让php自动增加和减少进程数，不过动态创建回收进程对服务器也是一种消耗。
参考:https://blog.51cto.com/xiaozhagn/2136667好了，处理完PHP的报错调优后，本以为一切终于可以正常了，没想到PHP是正常了，这下轮到了mysql的默认连接数问题了， 在PHP框架上产生了如下的报错：
[ error ] [10501]SQLSTATE[42000]: Syntax error or access violation: 1461 Can't create more than max_prepared_stmt_count statements (current value: 16382)
查看mysql如下3个参数值： Com_stmt_close prepare语句关闭的次数 Com_stmt_execute prepare语句执行的次数 Com_stmt_prepare prepare语句创建的次数 通过以下命令修改max_prepared_stmt_count的值（该值可动态修改，也可在配置文件中指定后重启服务生效）
[[email protected] ~]# mysql -hrm-wzsafaeeasdf.mysql.rds.aliyuncs.com -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 13412261
Server version: 5.7.14-AliSQL-X-Cluster-1.5.1.7-20200918-log Source distribution
Copyright (c) 2000, 2020, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> SHOW GLOBAL STATUS LIKE 'com_stmt%';
+-------------------------+------------+
| Variable_name | Value |
+-------------------------+------------+
| Com_stmt_execute | 1611653381 |
| Com_stmt_close | 1611634907 |
| Com_stmt_fetch | 0 |
| Com_stmt_prepare | 1611663970 |
| Com_stmt_reset | 0 |
| Com_stmt_send_long_data | 0 |
| Com_stmt_reprepare | 0 |
+-------------------------+------------+
7 rows in set (0.02 sec)
mysql> set global max_prepared_stmt_count=1048575;
ERROR 1227 (42000): Access denied; you need (at least one of) the SUPER privilege(s) for this operation
mysql> GRANT SYSTEM_USER ON *.* TO 'root'
-> ;
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'SYSTEM_USER ON *.* TO 'root'' at line 1
mysql> GRANT SYSTEM_USER ON *.* TO root
-> ;
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'SYSTEM_USER ON *.* TO root' at line 1
mysql> exit;
Bye
数据库参考：https://zhuanlan.zhihu.com/p/67188414
修改完后，以为全部问题解决了，没想到，又报了这“ERROR 1040 (HY000): Too many connections”mysql的链接数满了。
按MySQL sleep连接过多 解决办法，把超时等待时间设置短
elapse@luck:/var/www$ /usr/local/mysql/bin/mysql -uroot -p
Enter password:
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 31
Server version: 10.5.8-MariaDB MariaDB Server
Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MariaDB [(none)]> create user 'test'@'localhost' identified by 'test';
ERROR 1396 (HY000): Operation CREATE USER failed for 'test'@'localhost'
MariaDB [(none)]> set password for 'test'@'localhost' = 'test1';
ERROR 1372 (HY000): Password hash should be a 41-digit hexadecimal number
MariaDB [(none)]> grant all on *.* to 'test'@'localhost';
Query OK, 0 rows affected (0.001 sec)
MariaDB [(none)]> set password for 'test'@'localhost' = 'test1';
ERROR 1372 (HY000): Password hash should be a 41-digit hexadecimal number
MariaDB [(none)]> grant system_user on *.* to 'root';
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'on *.* to 'root'' at line 1
MariaDB [(none)]> show global variables like 'wait_timeout';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| wait_timeout | 28800 |
+---------------+-------+
1 row in set (0.001 sec)
MariaDB [(none)]> set global wait_timeout=30;
Query OK, 0 rows affected (0.000 sec)
MariaDB [(none)]> show global variables like 'wait_timeout';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| wait_timeout | 30 |
+---------------+-------+
1 row in set (0.001 sec)
MariaDB [(none)]> SHOW GLOBAL VARIABLES LIKE 'interactive_timeout';
+---------------------+-------+
| Variable_name | Value |
+---------------------+-------+
| interactive_timeout | 28800 |
+---------------------+-------+
1 row in set (0.001 sec)
MariaDB [(none)]> SHOW GLOBAL VARIABLES LIKE 'interactive_timeout';
+---------------------+-------+
| Variable_name | Value |
+---------------------+-------+
| interactive_timeout | 28800 |
+---------------------+-------+
1 row in set (0.001 sec)
MariaDB [(none)]> set global interactive_timeout=30;
Query OK, 0 rows affected (0.000 sec)
MariaDB [(none)]> SHOW GLOBAL VARIABLES LIKE 'interactive_timeout';
+---------------------+-------+
| Variable_name | Value |
+---------------------+-------+
| interactive_timeout | 30 |
+---------------------+-------+
1 row in set (0.001 sec)
MariaDB [(none)]>