[tensor]

The headline of this article bothered me in this regard. Node.js is decidedly middle of the pack in terms of performance:

http://www.techempower.com/benchmarks/

In addition to various JVM technologies, there are faster technologies in C++, PHP, and Lua.

[pekk]

I think you will find that in many actual applications PHP is not faster than Node.

Further, once you apply a framework to paper over some language warts, performance is often terrible and can only be rescued by extremely liberal caching.

If this were not so, it would be hard to see the motivation for HipHop.

[tensor]

Might the motivation simply be to get closer to C++ performance?

I really don't value this type of response where the benchmark is brought into question, yet nothing is substituted as evidence. In the few cases were someone does claim that they rewrote a sufficiently complex system in Node from some other language, it's impossible to discount that the performance changes come from architectural choices rather than language choices.

Playing devils advocate, I've heard the same claim you put forth here about Node.js: it gets much slower in real apps because you have more slow JS code being run vs the very fast C libraries that back the core of Node.js.

To me, benchmarks like the one I posted above are the most compelling form of evidence we have. What I take from it is that a great many "boring" languages and frameworks are really very fast. It's not the answer that most people want to hear of course; it goes against the current popular hype.