Perhaps the most significant performance problem spot in web apps is the database. In apps monitored by Scout, database queries account for nearly a third of the time spent in the average Rails web request. Just as important, the more time an app spends in the database, the more volatile its response times. Here's a breakdown:
||% of Response Time
||Correlation to Response Time Volatility
Data is based on apps monitored by Scout averaging 50 requests per-minute or higher.
The response time correlation measures the ratio of an app's 95th response time duration to the mean response time. This value may range from -1 to 1.
Database queries deserve some extra performance love, and our database monitoring addon is here to help.