- processing images
- providing API for warehouse fulfilment for online retailers (peak load is 100x of base load, latency goes out of the roof before Rails just crashes with OOM)
- real estate indexing with huge amount of data (we could not make the full text search work reliably with Rails)
These were pre 6.0 and I am pretty sure many things changed since, I am just saying it is easy to run into these situations. The bigger your framework the more assumptions are built in that are hard to come by. It is good for Basecamp startups not good for non-Basecamp startups.
Providing API for warehouse fulfilment with peak load 100x greater than base: Run your Rails APP in any number of possible auto-scaling configurations.
Real Estate Full Text Indexing: Use ElasticSearch alongside Rails to provide highly performant full text indexing/searching
- https://blog.codinghorror.com/performance-is-a-feature/
- http://www.nicolas-hahn.com/python/go/rust/programming/2019/...
But I really think there is a difference between framework/programming language performance and acceptance-level app performance.
It is possible to have a good performance app (Github, Shopify ) even if you don't believe that Ruby is good enough in this category.