I did the same thing when cutting over our old system to the new one: I fired an e-mail for every WARN in the system, including 404s that have always existed. 1

I did the same thing when cutting over our old system to the new one: I fired an e-mail for every WARN in the system, including 404s that have always existed. 1k+ emails that day plus GMail disabling SMTP from our server was the sign that e-mail is meant for alerts, not logging. We've since tried out and signed up with NewRelic with an extremely low error threshold of 0.01%. As a result, we have more data than we had in the past for our errors, notifications on when the threshold is crossed (not for each error), and, most importantly, less dev work to manage them.