PHP

What is PHP?

PHP (Hypertext Preprocessor) is a widely used open-source server-side scripting language designed for web development. It is embedded into HTML, making it easy to create dynamic web pages and applications. PHP executes on the server, generating content that is sent to the client’s browser. It integrates well with databases such as MySQL, PostgreSQL, and MariaDB, powering content management systems such as WordPress, Drupal, and Joomla. PHP is also commonly used to build Learning Management Systems (LMSs) such as Moodle.

Known for its simplicity, flexibility, and large community support, PHP runs on most operating systems and web servers. Despite newer languages emerging, PHP remains a core technology behind millions of websites worldwide.

How PHP works

PHP works as a server-side scripting language that processes code on the server before sending output to the client’s browser. Here’s how it works step by step:

1. Client Request

• A user types a URL (e.g., example.com/page.php) into their browser or submits a form.
• The request goes to the web server (like Apache, Nginx, or IIS).

2. Server Passes Request to PHP Engine

• The web server sees the .php file and forwards it to the PHP interpreter (engine).

3. PHP Code Execution

• The PHP engine executes the PHP code on the server. It can perform tasks such as:
• Accessing a database (MySQL, PostgreSQL, etc.)
• Processing form data
• Running business logic
• Including or generating dynamic content

4. Output as HTML (or JSON, XML, etc.)

• After execution, PHP generates output (usually HTML).
• The web server sends this processed result back to the client’s browser.

5. Browser Renders the Page

• The user only sees the final output (e.g., a web page), not the underlying PHP code.

PHP vs. HTML

PHP and HTML are different but often work together in web development. HTML is a markup language used to structure and display content in a browser. It is static, meaning the content does not change unless the code itself is updated. PHP, on the other hand, is a server-side scripting language that generates dynamic content before sending it to the browser, making web pages interactive and data-driven.

Benefits and Advantages of PHP

PHP has remained one of the most popular server-side scripting languages because of its flexibility, ease of use, and strong community support. Here are the main benefits and advantages of PHP: 

Open Source and Free: PHP is open-source, meaning it’s free to use with no licensing costs. Large community support ensures regular updates, security patches, and new features. 

Easy to Learn and Use: Simple syntax that resembles C and Java, making it beginner-friendly. Can be embedded directly into HTML, enabling dynamic page generation. 

Cross-Platform Compatibility: Runs on major operating systems (Windows, Linux, macOS) and integrates with popular web servers (Apache, Nginx, IIS). 

Strong Database Support: Native integration with databases like MySQL, PostgreSQL, Oracle, and MariaDB. Makes it ideal for developing data-driven websites and applications. 

Scalability and Performance: Suitable for both small websites and large, high-traffic applications. Can be optimized with caching tools and frameworks for better performance. 

Large Ecosystem and Frameworks: Rich ecosystem with frameworks such as Laravel, Symfony, and CodeIgniter that speed up development. Availability of ready-to-use libraries and plugins. 

Community and Documentation: Massive global community, extensive tutorials, and strong documentation make troubleshooting easier. 

Many users find PHP is cost-effective, flexible, and well-suited for building dynamic, database-driven websites and web applications at any scale. 

Disadvantages and Limitations of PHP

Here are the main disadvantages and limitations of PHP that developers and businesses should consider:

Security Concerns: Being open-source and widely used, PHP is a frequent target for hackers. Poorly written PHP code can be vulnerable to attacks like SQL injection, XSS, and CSRF if not handled properly.

Inconsistent and Old Syntax: PHP has evolved over time, which means older code can look messy and inconsistent. Mixing PHP directly with HTML can make code harder to maintain compared to more structured frameworks or modern languages.

Performance Limitations: While fine for most web apps, PHP is generally slower than compiled languages (like Java or C++) and some modern scripting languages (like Node.js for async tasks). Not ideal for CPU-heavy applications.

Weak for Large-Scale Applications (Without Frameworks): Raw PHP is harder to manage in complex projects without using frameworks such as Laravel or Symfony. Scaling enterprise applications often requires additional layers and tools (and of course the associated skilled staff).

Dependency on Community and Hosting Environments: Quality of third-party libraries and packages can vary. While PHP is widely supported, some modern cloud-native platforms prioritize languages like Node.js, Go, or Python.

What is PHP Application Monitoring?

PHP application monitoring is the process of tracking the performance, availability, and behavior of a PHP-based web application in real time. It helps developers and DevOps teams detect issues (like slow response times, errors, or bottlenecks), understand the root causes, and improve the overall reliability and user experience of the application.

Key Aspects of PHP Application Monitoring

Performance Metrics

When evaluating the performance metrics available in a monitoring tool, consider whether metrics pertaining to the infrastructure and beyond the application are available, metrics about hardware or cloud platforms and database metrics. Basic metrics you will want from PHP APM include:

• Response times (average, percentiles)
• Throughput (requests per second)
• Memory usage and CPU load
• Database query performance (e.g., MySQL, PostgreSQL)
• External API call / third-party service latency

Error Tracking

PHP application monitoring should track and alert on errors such as:

• PHP errors and exceptions (e.g., Fatal error, Notice, Warning)
• HTTP status codes (e.g., 500 Internal Server Error)
• Uncaught exceptions and stack traces

Availability Monitoring

PHP application monitoring should include measures of availability that can be leveraged to asses KPIs or used as SLOs to quantify SLA adherence. Typically APM tools will cover:

• Uptime and downtime tracking
• Health checks (ping, heartbeat endpoints)

User Experience Metrics

Beyond availability, PHP APM needs to monitor user experience. A slow web page can frustrate users and lead to eCommerce revenue losses. Key metrics and events to track include:

• Page load times
• Slow transactions
• Frontend (browser) monitoring if combined with JavaScript RUM (Real User Monitoring)

Synthetic Monitoring

Enterprise-grade application monitoring for PHP will usually include synthetic monitoring capabilities, whereby the monitoring platform will continuously simulate users accessing PHP sites from a variety of geographical locations to simulate real user behaviors. This type of monitoring helps administrators unearth issues when there are no real users using a site, often before any real users encounter issues. Learn more: Synthetic Transaction Monitoring | eG Innovations.

Distributed Transaction Tracing

Distributed Transaction Tracing allows you to monitor availability, response time, and errors for each transaction, hop-by-hop performance details, and analysis across multiple web applications; many monitoring platforms will support polyglot applications and support tracing across PHP, Java, and Microsoft .NET application tiers.

Code-level Visibility

Some PHP APM solutions, such as eG Enterprise, can offer code-level root-cause diagnostics that will pinpoint the PHP line of code to which failures or performance slowdowns can be attributed.