[ericb]

The Rails app I scaled posted half a meg of JSON on every save-request every 10-15 seconds. In Rails, we parsed it, converted some parts into HTML nodes in Nokogiri, sanitized it, and saved it to both mysql and cassandra.

It wasn't a problem other than that a better initial design (nothing to do with rails) could have made passing all that data not needed, which was better for mobile. We had about 600,000 customers.

[jupp0r]

How many requests per second are you talking about roughly? One major problem we face is that downstream services also have performance problems and have multi second response times. While waiting for the response, a whole rails worker is sitting idle, taking up hundreds of megabytes of memory for seconds.