When it comes to web hosting and server performance, the way your server processes dynamic requests determines how fast and reliable your website runs. Three major methods are CGI, FastCGI, and PHP-FPM. While they serve a similar purpose, their efficiency and scalability vary significantly.
In this guide, we’ll explore each, their differences, and which one is best for your website.
1. CGI (Common Gateway Interface)
CGI is one of the earliest standards for running dynamic web applications.
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How it works: For every request, the web server spawns a new process.
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Pros:
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Very simple to implement
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Works with multiple programming languages
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Cons:
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Extremely slow for high-traffic sites
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High CPU and memory usage due to spawning new processes
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👉 Best for legacy systems or very low-traffic sites.
2. FastCGI
FastCGI was developed to improve CGI’s inefficiency.
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How it works: Instead of creating a new process for every request, it keeps processes running and reuses them.
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Pros:
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Much faster than CGI
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Reduces server overhead
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Cons:
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More complex setup
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Idle processes may still consume memory
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👉 Ideal for medium to large websites where performance is important.
3. PHP-FPM (PHP FastCGI Process Manager)
PHP-FPM is an advanced version of FastCGI designed specifically for PHP.
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How it works: Manages pools of PHP worker processes with advanced features.
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Pros:
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Superior performance for PHP applications
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Process recycling prevents memory leaks
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Can assign dedicated pools to different apps/sites
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Better error handling and logging
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Cons:
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Only works with PHP-based applications
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👉 The best option for high-traffic PHP sites such as WordPress, Laravel, or e-commerce platforms.
4. Key Differences Table
| Feature | CGI | FastCGI | PHP-FPM |
|---|---|---|---|
| Process Handling | New process per request | Persistent reusable processes | Persistent, advanced pool management |
| Speed | Slow | Faster than CGI | Fastest & most optimized |
| Resource Usage | High | Moderate | Low/optimized |
| Best Use Case | Legacy apps, low traffic | Medium-large apps | High-traffic PHP-based sites |
5. Which One Should You Use?
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Avoid CGI unless you are running very old applications.
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FastCGI works well but is less efficient compared to PHP-FPM.
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PHP-FPM is the modern standard and should be your default for PHP-based hosting.
If you’re hosting on Sternhost, PHP-FPM is supported out of the box for maximum performance and stability.
Final Thoughts
CGI, FastCGI, and PHP-FPM all serve the purpose of processing server-side requests, but PHP-FPM stands out as the most efficient for today’s PHP-driven web.
👉 Want faster, more reliable hosting? Explore Sternhost’s optimized hosting plans today!
