Why are so many web languages interpreted rather than compiled?

Question

Why didn't languages such as C end up being using for web dev? Surely the speed increases from being compiled would be useful for heavy load sites?

Answer 1

Another good reason is that on a big server execution speed is not so much an issue as the connection speed anyway. Most of the time is spent sending and receiving data, not number crunching. And actually in certain web services which do a lot of computations, the hard crunching is probably run as a compiled program.

Plus interpreted languages don't need compiling (which on a large project can take time), thus it's more suited for the typically agile development of web solutions.

Answer 2

Most web applications talk to a database. The overwhelming majority of these apps spend almost all of their time communicating with the database. So, for any given request to the application, there is a tiny amount of processing in the application server and then a long pause while waiting for the database. Since such a small percentage of any request's time is spent in actual application server code, optimizing that code by writing it in C/C++ will gain only a tiny, likely not noticeable, improvement in response time.

So, rather than focusing on C/C++ and saving every last CPU cycle, it makes more sense to worry about developer productivity. Developers are very expensive. And, they're typically much more productive in a scripting language or even in Java than they are in C/C++.

Of course, there are exceptions to this. And if some requests to your application are CPU or memory intensive, they should be written in C/C++. But, for the rest of your application, you're better off focusing on optimizing your algorithms, data structures, communication with the database, and developer productivity than in optimizing your language.

Answer 3

Scripting languages have the following advantages over C:

1. Much faster development
2. Today, all of those relevant to this question are compiled at runtime. In some cases, this can make them faster than an equivalent C program, so performance just isn't an issue anymore.
3. Maintenance costs much less
4. You can develop using Agile methods (like unit tests) which results in much better code. Yeah, you can do that in C, too, but it's much more effort.
5. When you're doing web development, you have huge frameworks which do most of the work for you.
6. They are much more open to change. A new feature can take as much as a few minutes to implement.
7. If something is broken, you can login to your server, start a text editor in the console and fix the problem, sometimes without having to restart.