What does it mean to say that a framework “scales well”?

Question

When reading about frameworks (.net. ruby on rails, django, spring, etc.), I keep seeing so and so does or doesn\'t scale well.

What does it mean when someone says that

Answer 1

It means that a particular framework does (or does not) meet the increased demand that more users put on it. If you have an application written in VBScript, it might not do a good job of handling the 40,000,000 users of Facebook, for example.

This blog post explains some of the scalability pains Twitter experienced a year or so ago. It could provide some more insight into the answer to your question.

Sometimes lack of scalability is used to denigrate a language or framework, so watch out for that. Stick to studies that show real metrics. This applies to my VBScript example in the previous paragraph as well.