Is Rails Slow? I Built the Same Blog API Eight Times to Price the Framework
"Rails is slow" is an unanswerable question, because a Rails app and a Go app are never doing the same work. So I narrowed it: inside one runtime, what do the framework and the ORM cost? Four runtimes, each built twice, all returning identical JSON from the identical four SQL statements, measured three times on Docker Linux with MySQL. The magic tax in CPU per request came out at ×7.67 for Ruby, ×6.14 for Python, ×2.62 for Node and ×2.51 for Go — and I counted, object by object, exactly what Active Record builds on every request.