centos上查看max_connections

您可以通过以下命令来查看CentOS上的max_connections值：

1. 登录MySQL控制台 ：mysql -u 用户名 -p

2. 在MySQL中运行以下命令： SHOW VARIABLES LIKE 'max_connections';

这将显示当前MySQL服务器的max_connections值。如果需要更改此值，您可以使用以下命令来更改它：

SET GLOBAL max_connections = 500;

请注意，这仅会在运行时更改max_connections值，重启MySQL服务器后将恢复默认值。如果您想使更改永久生效，则需要在my.cnf或my.ini配置文件中更改该值。

相关问题

检查错误原因 creating directory /data/primary/gpseg0 ... ok creating subdirectories ... ok selecting default max_connections ... 750 selecting default shared_buffers ... 125MB selecting default timezone ... Asia/Shanghai selecting dynamic shared memory implementation ... posix creating configuration files ... ok creating template1 database in /data/primary/gpseg0/base/1 ... child process was terminated by signal 9: Killed initdb: removing data directory "/data/primary/gpseg0" 2023-06-08 08:53:53.568563 GMT,,,p22007,th-604637056,,,,0,,,seg-10000,,,,,"LOG","00000","skipping missing configuration file ""/data/primary/gpseg0/postgresql.auto.conf""",,,,,,,,"ParseConfigFile","guc-file.l",563, 20230608:16:54:12:021728 gpcreateseg.sh:VM-0-5-centos:gpadmin-[INFO]:-Start Function BACKOUT_COMMAND 20230608:16:54:12:021728 gpcreateseg.sh:VM-0-5-centos:gpadmin-[INFO]:-End Function BACKOUT_COMMAND 20230608:16:54:12:021728 gpcreateseg.sh:VM-0-5-centos:gpadmin-[INFO]:-Start Function BACKOUT_COMMAND 20230608:16:54:12:021728 gpcreateseg.sh:VM-0-5-centos:gpadmin-[INFO]:-End Function BACKOUT_COMMAND 20230608:16:54:12:021728 gpcreateseg.sh:VM-0-5-centos:gpadmin-[FATAL][0]:-Failed to start segment instance database VM-0-5-centos /data/primary/gpseg0 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:-End Function PARALLEL_WAIT 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:-End Function PARALLEL_COUNT 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:-Start Function PARALLEL_SUMMARY_STATUS_REPORT 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:------------------------------------------------ 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:-Parallel process exit status 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:------------------------------------------------ 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:-Total processes marked as completed = 0 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:-Total processes marked as killed = 0 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[WARN]:-Total processes marked as failed = 1 <<<<< 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:------------------------------------------------ 20230608:16:54:12:019435 gpinitsystem:VM-0-5-centos:gpadmin-[INFO]:-End Function PARALLEL_SUMMARY_STATUS_REPORT FAILED:VM-0-5-centos~6000~/data/primary/gpseg0~2~0

根据这个 error message，从日志中可以看出在创建 template1 数据库时出现了问题，initdb 进程被 signal 9 终止了，导致创建数据库失败，然后 gpinitsystem 进程也失败了。通常 signal 9 是操作系统发出的强制杀死进程的信号，这可能是因为进程占用了太多的内存或 CPU 资源，或者是由于其他系统问题导致的。

你需要检查系统资源使用情况，尤其是内存和 CPU 使用情况，以及系统日志，查找任何可能导致进程被强制终止的问题。如果你在检查过程中无法解决问题，可以向 Greenplum 社区或官方论坛求助。

*** Starting uWSGI 2.0.21 (64bit) on [Sat Jul 22 00:16:37 2023] *** compiled with version: 4.8.5 20150623 (Red Hat 4.8.5-44) on 21 July 2023 16:13:34 os: Linux-3.10.0-1160.88.1.el7.x86_64 #1 SMP Tue Mar 7 15:41:52 UTC 2023 nodename: VM-8-7-centos machine: x86_64 clock source: unix pcre jit disabled detected number of CPU cores: 2 current working directory: / detected binary path: /www/wwwroot/154.8.205.71/c2843d02b561ac15f07f4117c97425a0_venv/bin/uwsgi setgid() to 1000 setuid() to 1000 chdir() to /www/wwwroot/154.8.205.71 your processes number limit is 7908 your memory page size is 4096 bytes detected max file descriptor number: 1024 lock engine: pthread robust mutexes thunder lock: disabled (you can enable it with --thunder-lock) uWSGI http bound on 0.0.0.0:6359 fd 4 uwsgi socket 0 bound to TCP address 127.0.0.1:46421 (port auto-assigned) fd 3 Python version: 3.9.7 (default, Jul 21 2023, 22:55:57) [GCC 4.8.5 20150623 (Red Hat 4.8.5-44)] Python main interpreter initialized at 0x17f23d0 python threads support enabled your server socket listen backlog is limited to 100 connections your mercy for graceful operations on workers is 60 seconds mapped 166752 bytes (162 KB) for 2 cores *** Operational MODE: threaded *** unable to find "application" callable in file /www/wwwroot/154.8.205.71/weixin_stampingHub unable to load app 0 (mountpoint='') (callable not found or import error) *** no app loaded. going in full dynamic mode *** *** uWSGI is running in multiple interpreter mode *** spawned uWSGI master process (pid: 2931) spawned uWSGI worker 1 (pid: 2932, cores: 2) spawned uWSGI http 1 (pid: 2933)

根据你提供的日志信息，看起来uWSGI无法找到Django项目的可调用对象。这可能是由于以下原因之一造成的：

1. 可调用对象未正确配置：请确保`uwsgi.ini`文件中的`module`参数正确指向Django项目的可调用对象。例如，如果你的Django项目名称为`weixin_stampingHub`，将`module`参数设置为`weixin_stampingHub.wsgi:application`。

2. 可调用对象所在的文件路径错误：请检查`uwsgi.ini`文件中`module`参数指定的文件路径是否正确。确保路径是相对于项目根目录的，并且使用正确的模块和文件名。

3. 可调用对象的导入错误：可能由于导入错误而无法找到可调用对象。请确保在Django项目的入口模块（通常是`wsgi.py`文件）中正确导入了`application`对象。

请根据上述提示检查并修复相关配置问题，然后重新启动uWSGI服务器。如果问题仍然存在，请提供更多关于项目结构和配置文件的详细信息，以便我能够帮助你更好地解决问题。