3 ms·

While I think quite a few people use this, I question the actual benefits. People often argue with performance, but unless you spend a lot of work into doing th

While I think quite a few people use this, I question the actual benefits. People often argue with performance, but unless you spend a lot of work into doing things right, the general "C backend" won't outperform even simple things like nodejs ... at least once you reach the realm of ten-thousands of requests per second coupled with more than just a static page, "hello world" and a for-loop. Same goes for the "DBMS" part of things, being the bottleneck for the majority of real world applications anyway. I think the best use case would be some static content delivery coupled with a few dynamic pages and APIs backed up by SQLite here and there ... Some references would be cool I guess. Anyone?

10000truths 5y ago
You can easily serve 10000 static requests/second per core on a modern server grade CPU over TLS with nginx, which is written in C. Slap node.js and express on top and you might dip to something like half of that. But the real win with using C (or rather, using direct syscalls) comes from how much of that throughput you can retain while serving dynamic content. At least on Linux, performantly serving a static file would have a syscall flow similar to the following: file -> splice -> pipe -> splice -> kTLS socket The performance increase comes from copying the file to the socket without any detouring of the data via userspace. This can easily be adapted for the case where you need to inject portions of that file with dynamically retrieved content, by using offset fields in the splice call from the file being served, and manually writing to the pipe to inject the dynamic content. You cannot easily replicate this construct in any other dynamic-content server framework I know of - you have to do it manually in C (or any language that allows you to directly invoke system calls).

3 ms·

While I think quite a few people use this, I question the actual benefits. People often argue with performance, but unless you spend a lot of work into doing th

by numlock86 5y ago

10000truths 5y ago
You can easily serve 10000 static requests/second per core on a modern server grade CPU over TLS with nginx, which is written in C. Slap node.js and express on top and you might dip to something like half of that. But the real win with using C (or rather, using direct syscalls) comes from how much of that throughput you can retain while serving dynamic content. At least on Linux, performantly serving a static file would have a syscall flow similar to the following: file -> splice -> pipe -> splice -> kTLS socket The performance increase comes from copying the file to the socket without any detouring of the data via userspace. This can easily be adapted for the case where you need to inject portions of that file with dynamically retrieved content, by using offset fields in the splice call from the file being served, and manually writing to the pipe to inject the dynamic content. You cannot easily replicate this construct in any other dynamic-content server framework I know of - you have to do it manually in C (or any language that allows you to directly invoke system calls).