Ruby on Rails scalability is indeed a hot topic. First off and being utterly blunt, Alex is talking out of his ass, he clearly has no experience with building scalable web sites.
The way I see it, scalability is really more a platform and architecture challenge than a language specific problem. MySpace was originally written in ColdFusion, then upgraded to ASP, then .NET.
Check out this article on history of how MySpace scaled http://www.baselinemag.com/article2/0,1397,2082921,00.asp
The focus is to identify the bottlenecks (not just blinding blaming a whole language) and then adapting the architecture to deal with it. Developers and management alike tend to think that there is only 1 right architecture to scale, that’s so not true, every high volume website has their own unique set of challenges.
My account was suddenly canceled. I went through the procedure to restore it and it is still canceled in spite of the promise to restore it in a few moments. The 2 desperate messages to Twitter have not been answered.
This could be a solution for them, http://www.espace.com.eg/neverblock
This library would solve many of the concurrency issues held by Ruby. Regretfully the implementation done till now is for Ruby 1.9 as it builds over the fibers implementations in 1.9
@diego - You know that MySpace runs on ASP.NET, right? They’re probably around 2 billion page hits a day by now.
As others have pointed out, though, this has got to be all about the database. This is a simple app with very little processing. The majority of the load is in the database. Language speed probably has little to do with it.