It takes longer to access data stored on your hard disk vs. RAM . But how big is the difference? It’s really big. How can you tell if you your web application is being impacted by slow disk access? What impacts I/O performance? What’s the best path to fixing the ... Read more

John P. Wood of Signal , which offers a mobile customer engagement platform used by many top brands, recently created a couple of Scout Plugins for monitoring CouchDB . I’ve always been impressed by the team at Signal, so I was curious how they were using CouchDB in production. It ... Read more

Photo by mollypop My how you’ve grown! A couple of years ago your little Rails app was on a single server. Now you’re on a whole cluster – you’ve got web servers, database servers, HAProxy servers, and more. I’m so proud of you! Monitoring your Rails cluster has gotten more ... Read more

When checking the amount of free memory on a Linux server, it’s easy to think you’re running out of memory when you’re not. For example, here’s the output of free -m on a server with 4GB of RAM : With a quick glance, you might start sweating. Only 39 MB ... Read more

A big part of providing good support is making it painless. At Scout , Andre and I handle all of the support requests. Once we’ve gathered the account information, it usually doesn’t take much time to help. The problem is quickly putting the account information together. We don’t want to ... Read more

UPDATED 6/7/2013 – We no longer recommend using bash -l -c to run Cron jobs with RVM . See our updated approach . This info is for Scout users, but it’s also applicable to anyone who’s wondered how to use cron together with RVM . This assumes 1) you are ... Read more

I was back in Michigan a few weeks ago visiting family. These trips always involve a “what do you do?” question at some point. I’m never sure how to answer. “I have a startup.” Honestly, I don’t think of Scout as a startup. Scout is a business built the old-fashion ... Read more

If you’ve used Major Hayden’s MySQLTuner before, you know it’s a great source of MySQL optimization tips. Now you can get MySQLTuner reports automatically delivered through Scout. All you need to do is install the MySQL Stats w/MySQLTuner plugin , or update the plugin if you already have it installed. ... Read more

Updated 3/21/2013 – The MongoDB Overview plugin discussed below has been split into 2 separate plugins: MongoDB Server Status and MongoDB Database Stats . The server status plugin reports global MongoDB metrics and the database stats plugin reports metrics specific to a particular database. John Nunemaker of Ordered List knows ... Read more

You maintain a growing Rails application and you’re seeing something peculiar. Sometimes when you use the application, it feels like the performance deteriorates significantly. However, all of your performance data shows no issues – requests in the Rails log file look speedy, CPU utilization is fine, database performance is solid, ... Read more