为什么在访问同一个项目的时候会有时快有时非常慢?用的是Yii
Yii PHP
在访问一个项目比如说http://host/module/controller/ action的时候，js、img、css等都能在0.2秒内加载完，但是视图文件html有时能在0.2秒内加载完成，有时则需要2秒以上甚至30秒才能加载完成。这种情况会发生在我首次访问这个地址时，或者我访问该控制器下的另一个视图如http://host/module/controller/ anotheraction后再重新访问 action这个地址时，并且这种情况不只存在在action这一个地址，有可能会在anotheraction上发生。请问这是我代码的原因吗？我是用CDbCriteria来作为数据提供者
回复讨论(解决方案)
第一次访问慢 第二次快 这种情况一般是因为第二次直接读取了缓存
因此你应该把注意力放在为什么(第一次)会慢上
是否用了太多或者不太优良的sql语句
第一次访问慢 第二次快 这种情况一般是因为第二次直接读取了缓存
因此你应该把注意力放在为什么(第一次)会慢上
是否用了太多或者不太优良的sql语句
没有使用缓存，这里的”第一次“和”第二次“其实只是一个形义 的说法，理解成”间歇性“访问慢吧
那换个思路
你访问一个内容足够少的页面 比如PHP没有进行任何运算 前台页面只有个123 还会偶尔超慢吗?
如果不会,那就是你这个页面代码有问题 发关键代码来分析
如果这样也会慢,那再考虑其他思路
访问数据库时快时慢，这是很正常的现象，尤其是在单机测试环境下
操作系统都会将空闲的服务挂起（甚至将其移到硬盘，释放其所占内存）
如果你发起访问时，恰好 mysql 被移动到了硬盘，这就会有一个从硬盘读取并恢复现场的工作，当然要多花一点时间的
在正式运营的网站中，因为总是有人访问，所以总是不会被挂起。所以表现出来的效果也会令人满意
访问数据库时快时慢，这是很正常的现象，尤其是在单机测试环境下
操作系统都会将空闲的服务挂起（甚至将其移到硬盘，释放其所占内存）
如果你发起访问时，恰好 mysql 被移动到了硬盘，这就会有一个从硬盘读取并恢复现场的工作，当然要多花一点时间的
在正式运营的网站中，因为总是有人访问，所以总是不会被挂起。所以表现出来的效果也会令人满意
蛋疼的是，就是在正式运营的情况下出现这种情况，非常严重。代码方面也作了检查，问题不大。
因为这个项目有一定的时效性，所以数据库用的是外网的主库，读写都操作的是主库，但只有几个人在使用这个项目，操作也不会特别频繁。别的项目也有会频繁访问数据库的，但都做了读写分离。
诡异的是，这个项目下比如说有一个”分类管理“的菜单，链接指向的是一个展示分类数据的视图页，分类表里面只有5个字段10条记录，查询显示出来应该来说是非常快的。但是有时候想要打开这个页面也会花上几秒甚至分钟！
我还查看了慢查询日志，里边像一条这样的sql语句他的查询时间也会使用到15秒之久，”UPDATE history SET status='1313',time=1373254836,t_id='34' WHERE id='817';“,求解。。
你有很多update吗?
会不会是引起了锁表所以很慢
你有很多update吗?
会不会是引起了锁表所以很慢
今天打开CWebLogRoute，查看程序的执行情况，有了新的线索
刚发现，就截图上来了，还没开始着原因
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
Alipay PHP SDK transfer error: How to solve the problem of 'Cannot declare class SignData'?
Apr 01, 2025 am 07:21 AM
Alipay PHP...
Explain JSON Web Tokens (JWT) and their use case in PHP APIs.
Apr 05, 2025 am 12:04 AM
JWT is an open standard based on JSON, used to securely transmit information between parties, mainly for identity authentication and information exchange. 1. JWT consists of three parts: Header, Payload and Signature. 2. The working principle of JWT includes three steps: generating JWT, verifying JWT and parsing Payload. 3. When using JWT for authentication in PHP, JWT can be generated and verified, and user role and permission information can be included in advanced usage. 4. Common errors include signature verification failure, token expiration, and payload oversized. Debugging skills include using debugging tools and logging. 5. Performance optimization and best practices include using appropriate signature algorithms, setting validity periods reasonably,
How does session hijacking work and how can you mitigate it in PHP?
Apr 06, 2025 am 12:02 AM
Session hijacking can be achieved through the following steps: 1. Obtain the session ID, 2. Use the session ID, 3. Keep the session active. The methods to prevent session hijacking in PHP include: 1. Use the session_regenerate_id() function to regenerate the session ID, 2. Store session data through the database, 3. Ensure that all session data is transmitted through HTTPS.
What are Enumerations (Enums) in PHP 8.1?
Apr 03, 2025 am 12:05 AM
The enumeration function in PHP8.1 enhances the clarity and type safety of the code by defining named constants. 1) Enumerations can be integers, strings or objects, improving code readability and type safety. 2) Enumeration is based on class and supports object-oriented features such as traversal and reflection. 3) Enumeration can be used for comparison and assignment to ensure type safety. 4) Enumeration supports adding methods to implement complex logic. 5) Strict type checking and error handling can avoid common errors. 6) Enumeration reduces magic value and improves maintainability, but pay attention to performance optimization.
Describe the SOLID principles and how they apply to PHP development.
Apr 03, 2025 am 12:04 AM
The application of SOLID principle in PHP development includes: 1. Single responsibility principle (SRP): Each class is responsible for only one function. 2. Open and close principle (OCP): Changes are achieved through extension rather than modification. 3. Lisch's Substitution Principle (LSP): Subclasses can replace base classes without affecting program accuracy. 4. Interface isolation principle (ISP): Use fine-grained interfaces to avoid dependencies and unused methods. 5. Dependency inversion principle (DIP): High and low-level modules rely on abstraction and are implemented through dependency injection.
How to debug CLI mode in PHPStorm?
Apr 01, 2025 pm 02:57 PM
How to debug CLI mode in PHPStorm? When developing with PHPStorm, sometimes we need to debug PHP in command line interface (CLI) mode...
How to send a POST request containing JSON data using PHP's cURL library?
Apr 01, 2025 pm 03:12 PM
Sending JSON data using PHP's cURL library In PHP development, it is often necessary to interact with external APIs. One of the common ways is to use cURL library to send POST�...
Explain late static binding in PHP (static::).
Apr 03, 2025 am 12:04 AM
Static binding (static::) implements late static binding (LSB) in PHP, allowing calling classes to be referenced in static contexts rather than defining classes. 1) The parsing process is performed at runtime, 2) Look up the call class in the inheritance relationship, 3) It may bring performance overhead.
