What is oink?

Oink is a tool for Ruby on Rails applications that helps you figure out which parts of your app are consuming a lot of memory. When a web app slows down or crashes because it is using too much server memory, it can be very difficult to pinpoint exactly which user action caused the spike. This tool tracks memory usage and database activity for every request, then analyzes your log files to highlight the specific pages or actions that are the worst offenders. The tool works in two stages. First, while your application is running, it quietly records how much memory each web request uses and writes that information to a log file. Second, after you have collected some data, you run a command-line tool that reads through those logs and compares the memory usage to a limit you set. For example, you can ask it to flag any single request that increased memory usage by more than 75 MB. The results give you a clear picture of where your memory problems live. It shows you a ranked list of the ten worst individual requests, so you can see exactly which URLs caused the biggest spikes. It also tallies how many times each specific action crossed your threshold, which helps you spot patterns. If a particular page is causing memory problems every time a user visits it, that action will rise to the top of the list. You can also run it in a verbose mode that prints the full log details for every flagged request, giving you deeper context for debugging. This tool is built for developers and site reliability teams managing Rails applications that are experiencing performance issues related to memory. If your app keeps running out of memory and you do not know why, this tool helps you stop guessing and start looking at the actual data. It is particularly useful for applications with a lot of traffic, where identifying a single misbehaving page out of thousands of requests would otherwise be like finding a needle in a haystack.