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0 pointstoast08mo ago0 comments

Typically I've run cgi from a directory outside the document root. That's easy, and I think was the defaults?

That said, fork+exec isn't the best for throughput. Especially if the httpd doesn't isolate forking into a separate, barebones, child process, fork+exec involves a lot of kernel work.

FastCGI or some other method to avoid forking for each request is valuable regardless of runtime. If you have a runtime with high startup costs, even more so.

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SahAssar8mo ago

> FastCGI or some other method to avoid forking for each request is valuable regardless of runtime. If you have a runtime with high startup costs, even more so.

What's the point of using FastCGI compared to a plain http server then? If you are going to have a persistent server running why not just use the protocol you are already using the semantics of?

toast0OP8mo ago

I don't generally want or need my application server to serve static files, but I may want to serve them on the same hostname (or maybe I don't).

There's potential benefits for the httpd to manage specifics of client connections as well: If I'm using a single threaded process per request execution model, keep-alive connections really ruin that. Similarly with client transfer-encoding requests, does my application server need to know about that. Does my application server need to understand http/2 or http/3?

You could certainly do a reverse proxy and use HTTP instead of FastCGI as the protocol between the client facing httpd and the application server... although then you miss out on some speciality things like X-Sendfile to accelerate sending of files from the application server without actually transferring them through sockets to the httpd. You could add that to an http proxy too, I suppose.

SahAssar8mo ago

> You could certainly do a reverse proxy and use HTTP instead of FastCGI as the protocol between the client facing httpd and the application server

That's what I meant. Things like X-Sendfile (or X-Accel-Redirect in nginx) works with http backends. Why involve a different protocol to transfer a HTTP request to a backend instead of... HTTP? I really don't get the point of FastCGI over plain HTTP when a reverse proxy is talking to a upstream backend server.

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0 pointstoast08mo ago0 comments

Typically I've run cgi from a directory outside the document root. That's easy, and I think was the defaults?

That said, fork+exec isn't the best for throughput. Especially if the httpd doesn't isolate forking into a separate, barebones, child process, fork+exec involves a lot of kernel work.

FastCGI or some other method to avoid forking for each request is valuable regardless of runtime. If you have a runtime with high startup costs, even more so.

0 comments

SahAssar8mo ago

> FastCGI or some other method to avoid forking for each request is valuable regardless of runtime. If you have a runtime with high startup costs, even more so.

What's the point of using FastCGI compared to a plain http server then? If you are going to have a persistent server running why not just use the protocol you are already using the semantics of?

toast0OP8mo ago

I don't generally want or need my application server to serve static files, but I may want to serve them on the same hostname (or maybe I don't).

SahAssar8mo ago

> You could certainly do a reverse proxy and use HTTP instead of FastCGI as the protocol between the client facing httpd and the application server

1 more reply

j / k navigate · click thread line to collapse