What is "fastcgi"

The Fastcgi protocol defines how information is passed between the Web server and an external Fastcgi application. When a request is sent, the Web server starts a Fastcgi application to process it and generate dynamic responses that will be sent back to the client. Fastcgi applications process HTTP requests and each one consists of a collection of process pools. In pools, each process handles requests one at a time and, after completion, returns to the pool until it receives another request.

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