查询量一大经常出现502 bad Gateway,该如何处理-PHP Tutorial-php.cn

Home

Backend Development

PHP Tutorial

查询量一大经常出现502 bad Gateway,该如何处理

WBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWB

Jun 13, 2016 am 11:59 AM

fastcgigatewaynbspnginx

查询量一大经常出现502 bad Gateway
查了几百万条数据就直接nginx 502 Bad Gateway了。另一台服务器好好的。我不能登录服务器查看配置。请教各位弄过nginx+php的同志。你们服务器的设置都是啥样的？我发给硬件部的瞅瞅
------解决方案--------------------
502通常就是php-fpm歇菜了。这可能是由于fpm的连接数过大，或者程序的执行时间较长。
不过就凭你一句 查了几百万条数据就直接nginx 502 Bad Gateway了。 轻描淡写，没人能做到对症下药
------解决方案--------------------
内存不足，连接数太高，cpu满载以至于无法及时处理新连接，都可能导致这个502
就你这一句的确没办法知道具体情况
------解决方案--------------------
你们技术部的也太菜了吧！一次查几百万的数据
------解决方案--------------------
我这刷新的时候也出现502，也是nginx+php ，，配置的时候nginx里面也有设置：访问时间（如下）等几个参数把这几个参数的时间  设置长一些，再一个可能是你在nginx 搭建的时候资源可能不够，希望对你有帮助！
我这是偶尔出现这种情况，让运维重启一下服务就行了

fastcgi_buffer_size           128k;
fastcgi_buffers             8 128k;
fastcgi_busy_buffers_size     128k;
fastcgi_temp_file_write_size  128k;
------解决方案--------------------
php慢了，nginx请求半天得不到回应，自然会超时。看看有没有timeout的配置，关于fastcgi的

Statement

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

What are some common problems that can cause PHP sessions to fail?Apr 25, 2025 am 12:16 AM

Reasons for PHPSession failure include configuration errors, cookie issues, and session expiration. 1. Configuration error: Check and set the correct session.save_path. 2.Cookie problem: Make sure the cookie is set correctly. 3.Session expires: Adjust session.gc_maxlifetime value to extend session time.

How do you debug session-related issues in PHP?Apr 25, 2025 am 12:12 AM

Methods to debug session problems in PHP include: 1. Check whether the session is started correctly; 2. Verify the delivery of the session ID; 3. Check the storage and reading of session data; 4. Check the server configuration. By outputting session ID and data, viewing session file content, etc., you can effectively diagnose and solve session-related problems.

What happens if session_start() is called multiple times?Apr 25, 2025 am 12:06 AM

Multiple calls to session_start() will result in warning messages and possible data overwrites. 1) PHP will issue a warning, prompting that the session has been started. 2) It may cause unexpected overwriting of session data. 3) Use session_status() to check the session status to avoid repeated calls.

How do you configure the session lifetime in PHP?Apr 25, 2025 am 12:05 AM

Configuring the session lifecycle in PHP can be achieved by setting session.gc_maxlifetime and session.cookie_lifetime. 1) session.gc_maxlifetime controls the survival time of server-side session data, 2) session.cookie_lifetime controls the life cycle of client cookies. When set to 0, the cookie expires when the browser is closed.

What are the advantages of using a database to store sessions?Apr 24, 2025 am 12:16 AM

The main advantages of using database storage sessions include persistence, scalability, and security. 1. Persistence: Even if the server restarts, the session data can remain unchanged. 2. Scalability: Applicable to distributed systems, ensuring that session data is synchronized between multiple servers. 3. Security: The database provides encrypted storage to protect sensitive information.

How do you implement custom session handling in PHP?Apr 24, 2025 am 12:16 AM

Implementing custom session processing in PHP can be done by implementing the SessionHandlerInterface interface. The specific steps include: 1) Creating a class that implements SessionHandlerInterface, such as CustomSessionHandler; 2) Rewriting methods in the interface (such as open, close, read, write, destroy, gc) to define the life cycle and storage method of session data; 3) Register a custom session processor in a PHP script and start the session. This allows data to be stored in media such as MySQL and Redis to improve performance, security and scalability.

What is a session ID?Apr 24, 2025 am 12:13 AM

SessionID is a mechanism used in web applications to track user session status. 1. It is a randomly generated string used to maintain user's identity information during multiple interactions between the user and the server. 2. The server generates and sends it to the client through cookies or URL parameters to help identify and associate these requests in multiple requests of the user. 3. Generation usually uses random algorithms to ensure uniqueness and unpredictability. 4. In actual development, in-memory databases such as Redis can be used to store session data to improve performance and security.

How do you handle sessions in a stateless environment (e.g., API)?Apr 24, 2025 am 12:12 AM

Managing sessions in stateless environments such as APIs can be achieved by using JWT or cookies. 1. JWT is suitable for statelessness and scalability, but it is large in size when it comes to big data. 2.Cookies are more traditional and easy to implement, but they need to be configured with caution to ensure security.

See all articles