With Rails, do 500 errors slow down my application?

Question

I'm using Sentry to track errors on my Rails application. I have thousands of exception for low priority issues which I typically defer in fixing. My question is, do 500 errors impact performance for other users?

In theory, does it take longer to process an error/write it to log than it does for a 200 request? I'm trying to figure out if I should prioritize fixing 500 errors more.

Answer 1

Normally, it would not slow down your app: the 500 error will stops Rails' usual execution (ex: controller logic, view rendering, etc). This is most likely less expensive in resources than just writing a log file.

That been said, errors in the 500 range are server-side errors, which should be minimised as much as possible. You might want to aggregate your error logs and fix the most recurrent errors. In a UX perspective, server-side errors are pretty annoying and can make the end-user lose their trust in your app.

Answer 2

500 errors speed up you application. You don't have to priorize your resources on fixing low priority issues.