A nonsensical question that is rarely qualified.
Languages aren’t slow; implementations of languages are.
Language selection and scalability have little to do with each other; architectural design and implementation strategy dictate how scalable a final product will be.
I couldn’t have put it better myself.
The point is simple.
Just because a given language may be slower (note the “er”, that makes this a relative term) in parsing XML doesn’t mean that
- it’s fundamentally slow (an absolute term),
- that as part of a web stack it can’t do 10,000 requests/second, and
- simply tells you something about it’s performance in a given situation not about it’s “scalability”.
In case you’re wondering, I just got off a call where I was asked this question not about Ruby but about Java. Interesting.