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Comment by antirez | Hacker News Reader

In order to perform such a comparison you can't write three small trow-away programs, you need to optimize each version at your best for weeks to start to be meaningful, and you need an expert in the three systems.

Otherwise the test is still interesting but is: "what is the best language to write a memcached clone without being an expert in a given language, using a few hours", that still says something about how different the three languages are, but does not say much about what is the best language to implement the system.

Btw in a more serious test another parameter that you did not considered much is very important, that is, memory usage per-key in the three versions, and in general, memory behavior.

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Yeah, a brief look at his buffering code raised alarms all over the place for me. The use of dynamic memory allocation; the use of strlen to find out if the current buffer is empty - seriously? memset()'ing the entire buffer instead of bothering to zero out just the by after the end of the recv(). That's ignoring various bugs and other stuff.

I haven't looked at the rest of the code, but if it's anything like the buffering code this is nothing like what you'd expect to see in a decent C implementation.

It's fairy enough to demonstrate that the Go version makes it easy to write decent performing code, but the C version is atrocious (though to his credit it does at least buffer - I've seen so much C networking code that murders performance by doing small read()'s that I want to cry, including for the longest time the MySQL client library).

Of course part of his criticism is also down to not bothering to look for the plethora of C networking libraries that does this and does it well.

As the author points out in the article, the neat thing is that Go does this for you. That was the major takeaway.

This is the default programming model in Go, but it's the same for Node.js, and you can use an easy-to-use event library in Ruby and Python as well.

A key-value store is system programming. It should be carefully designed, it's not real-world that you accept the default I/O model of the language you are going to use.

p.s. in the case of C it's hard to argue what is the default I/O model. It supports threads, fork, multiplexing, blocking and non blocking I/O, in the same way basically (in a low level way).

In the real world, defaults and simple-to-use libraries (i.e. not twisted) matter. Just because you are doing system programming doesn't mean you necessarily have the time/skill to carefully optimize everything.

System's programming isn't just writing a KV store used by millions. Sometimes it's writing a dedicated calculation server used in a single company. Carefully optimizing your I/O model might take longer than doing the project itself.

There is no default in C, beyond stdio. The C specification makes no reference to any I/O beyond stdio.

The author was being unfair to C. Use epoll or, better yet, libuv. libuv is a simple-to-use library.

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