I realized why I was so aggressive in attempts to guide one of the latest StackOverflow questions so it would gain useful answers and wouldn't be closed as subjective. The question title is "Why are most really fast servers written in C instead of C++", and I really wondered why they are. Because that's... a bit personal to me. So, let me tell you this story.
Some time ago, after I suffered a fiasco to get a job in the USA, I thought it was a good idea to change my career to a less ivory-tower-ish. I thought about what was going on in the industry, and decided that since everything was moving to web, it would be a fruitful choice to become a web server developer. So I sent my resume to three companies that were hiring a newbie Linux C++ web server developer. Being under impression of "Smart and Gets things done" stuff, I wrote a resume that way and explicitly stated that I don't know anything about web serving.
One company, which is the top Russian search engine, declined me with a note "Your skills are valuable, but we can't offer you a job now" (bold is mine). I still wonder what that means: am I good or bad? Should I get more experience and try again or that's just a polite rejection? But well, alright, that's the number-one company, so I didn't frown upon that.
The other company was an emerging startup. They had a shiny big office with free coffee, and a large restroom (at least that's what they said). A sign of warning was that the team failed its previous startup, but hell, why not give it a try? I was contacted by the CEO (it's a small startup, isn't it? Anyway in one Silicon Valley startup I was also interviewed by a CEO, so that didn't bother me) and was sent a sample task.
The task was to develop a C++ anti-DDOS module that drops any IP that exceeds a connection limit per a prespecified time. The task had been sent without any prior notice, and had a week-long time limit (who cares that I have plans for the week?). Period.
Well, alright. I didn't have any experience with Apache and web serving at all, so I started googling like crazy. After five hours of googling, I learned how to create apache2 modules, I devised a way to create a C++, not a C, module and I wrote a module that worked but was thread-local (apache starts a lot of threads). Essentially it was useless, but, well, spending more than 5 hours for a job application is a commonly acknowledged overkill!
I thought it did prove that I was a fast learner and a capable programmer. I sent that solution with notes how it should be improved to make up a complete module. However, "the architect was not satisfied with my code," and I was asked to finish what I had been assigned to. A note that I already had invested enough time for them to see if I was capable good enough to do the job was replied with a hilarious letter. It happens that I don't profess the company's philosophy that values result rather than capability! And unless I finish the code I'm not accepted.
The startup I applied to has, I guess, already failed; they still are not spoken about--whole google output is their SEO technologies. And they still require a registration on their website to all applicants--pathetic, isn't it?
Well, if the company values working for it for free, then it indeed is of a different philosophy than me. Good luck to these guys, I hope they won't fail many startups until they learn something.
The reasons why I don't and won't apply to Google deserve a separate post, I think.
The third was another top Russian Internet company. They assigned an interview in their shiny big office with free a pong table, PS3 avaliable, as well as the usual free coffee and a large restroom! The interview started with a question "Why didn't you apply to Google?" -- apparently because of my Summer of Code participation (or because I was a candidate to replace a guy who transferred to Google from there).
The interview went smoothly, even considering that I didn't know anything about how HTTP or web servers work. After more usual questions, I was given a coding assignment. The clouds started gathering: they asked to write a C program to parse apache log and detect how many different IP addresses were in it. "Why not C++?" I asked, "it's easy and fast in C++!" The reply was that they wanted to judge my algorithm skills, not the knowledge of standard libraries. Well, OK, that seemed fair.. So, let's reckon how I did it in programming contests... *rubbing hands*
In 20 minutes the program was ready, but the remote server I was ssh-ed to suddenly went out of space, and the source somehow managed to get erased after a failed attempt to save it (Vim let me down this time). I spent another 20 minutes to code it again; it was all OK, and the interviewer even didn't see anything to criticize my code about.
The interview seemed to have gone great. The architect that interviewed me happened to come from the same university as me, was a fan of Vim as well, and sounded pleasant. We proceeded to discussing my salary, I made an offer, and there it happened.
"Okay, now I must confess," the architect started, "We lied to you a bit. All our software is actually written in C. Although we were looking for a C++ developer, you'll have to do C programming mostly."
The thing, yet unknown to the interviewer, is that I hate C; I hate it as much as I love C++. Feeling so deceived, I burst into explaining that writing in C is disgusting, since C is the new assembler, regardless of that I can do it quite well... No wonder I didn't get this job either.
Of course, I asked why they did development in C. And the answer was, "well, we sometimes feel urges to start rewriting it all in C++, module by module. But then we question ourselves—"but why?", and leave things as they are".
And now I also question myself—"why?" The fact that servers are mostly developed in C, I think, was crucial for my life. Perhaps, if it weren't the case, I would already have said goodbye to science and my masters studies, and would become a full-time corporate server developer. But sometimes at nights I still wonder why... why didn't they rewrite it in C++? And that's why I wanted that SO question answered.
Author Paul Shved
Modified April 9, 2010
License CC BY-SA 3.0