A database is a shared resource for a Rails application. A single misbehaving query hitting your database can slow down unrelated queries throughout your system. When we began running our own database monitoring against our apps, we discovered several expensive queries that weren't apparent when viewing individual web endpoints and ... Read more

Rails Postgres Guru Greg Navis shares another powerful tip. Greg is writing The Ultimate Guide to Deploying Rails on Heroku. Subscribe to his mailing list for performance tips & tricks. In my previous article on Postgres Trigrams , we used pg_trgm to speed up LIKE and other operators (even on ... Read more

The latest release (0.3.0) of Scout's Elixir APM package adds the ability to monitor GenServer calls. What is GenServer and how do you monitor it? A short intro to GenServer If you're coming from a Ruby background, you've probably used Sidekiq or similar to do background work outside of the ... Read more

Are folks upgrading to Rails 5? Where is the Postgres vs. MySQL battle heading? Are devs embracing Puma and concurrency? If you're curious about the above, you've come to the right place. We collect gems used on the apps we monitor at Scout to assist with debugging issues and to ... Read more

This is a guest post by Tomasz Kowal, a software developer currently working full time with Elixir at ClubCollect. He started with Erlang 6 years ago and is still amazed by the power functional languages provide. In his free time he likes tinkering with flying robots. Have you ever reached ... Read more

DevTrace is a performance widget for your Rails applications in development. It sits unobtrusively in the corner of your page, just waiting to drop insight on your application: See stack traces, SQL timings, and more with just a click! This kind of insight is powerful. You can see how your ... Read more

There's nothing quite like having a "tool-belt" full of tricks for getting the most performance out of your Rails app. This week, Rails Postgres Guru Greg Navis shares another powerful tip. A few months ago, I was working on a project that had about 100,000 users. Each user could have ... Read more

"An ounce of prevention is worth a pound of cure."• Benjamin Franklin Application performance problems can be annoying. With luck, you'll spend an hour or two resolving the problem and get back to your real job: building things. But what happens when the issues start piling up? What happens ... Read more

Most Rails engineers know the basics of database performance. They know that if a query is slow, an index may be the solution. Some know the trade-offs between having and not having an index. Or why an index on a low-cardinality column might not help. But everyone is surprised when ... Read more

Donald Knuth wrote an often quoted paper in the 70s which is still referenced when talking about performance in web apps today. Premature optimization is the root of all evil. In my line of work, it is sometimes invoked as a sort of apology; an excuse for why more time ... Read more