Editing Web server (section)

=== Software efficiency ===
The '''specific web server [[software design]] and model adopted''' (e.g.):
* single [[Process (computing)|process]] or multi-process;
* single [[Thread (computing)|thread]] (no thread) or multi-thread for each process;
* usage of [[coroutines]] or not;
... and other '''programming techniques''', such as (e.g.):
* minimization of possible [[Cache miss|CPU cache misses]];
* minimization of possible [[Branch misprediction|CPU branch mispredictions]] in critical paths for speed;
* minimization of the number of [[system call]]s used to perform a certain function / task;
* other tricks;
... used to implement a web server program, '''can bias a lot the [[Computer performance|performance]]s''' and in particular the '''[[scalability]] level''' that can be achieved under '''heavy load''' or when using high end hardware (many CPUs, disks and lots of RAM).

In practice some web server software models may require more OS resources (specially more CPUs and more RAM) than others to be able to work well and so to achieve target performances.