What things do Ruby or Rails not handle well? Are there any situations or cases that they're suboptimal for?

I'm trying to come up with things that Ruby (or 开发者_如何学JAVARails) either doesn't handle well, or things that are way too hard to do in Ruby.

So far I'm having a tough time, but I figured some people on here MUST have know some things that Ruby or Rails don't handle too well. Anyone?

Ruby is a language. Rails is a framework. Many of the things Rails isn't good at, such as anything not relating to a web framework, Ruby handles with ease.

The other question of what Ruby as a language is not good at is simple. Anything extremely performance intensive is probably better written in C. Ruby won't run natively on most smart phone devices so mobile apps are out. Ruby is not designed for embedded devices, so powering the next space shuttle launch is also a no go. Furthermore the lack of a maternal instinct make Ruby a bad choice to watch young infants.

There is nothing, it's simply perfect. ;-)

Ok, some downsides:

• Ruby has questionable parallelism and threading support. See for more details: http://www.igvita.com/2008/11/13/concurrency-is-a-myth-in-ruby/
• Windows support isn't up to par since most Ruby developers simple don't care (like me)

The stuff you'll most commonly hear about scaling issues is a myth. Unless you're making a second twitter perhaps.

There's very little you flat-out couldn't do in Ruby, but there's a few things you wouldn't want to do, mainly involving highly numerical computation. For most of those you could easily write a binding to a C-based API (or some other more performant library.) Image processing, for example, is something that would be dog slow for any non-trivial example in pure Ruby, but you can use RMagick to do it, which is a binding to the much-faster ImageMagick library.

Just about any other use for Ruby is fair game. I've written GUI apps with it, a lot of system services and more one-off scripts than I could count.

Well, it's a framework, so it optimizes for the most common cases. If your app requires unordinary and bizarre things (eg huge performance requirements, needs to use non-Ruby libraries), then Rails might not be suitable.

It seems to me that whenever a company hits these cases (usually performance rather than functionality or integration with other systems) they have to write their own stuff - Google has Big Table, Facebook has their own webserver, etc.

If you're in this position, you're most likely rolling in money and spending some of it to rewrite your code isn't going to be an issue.

However, Rails is great for most normal apps! I don't think it has any gaps that might cause pitfalls in normal cases.