In this new post from Abhinav Singh on how to use file locking to keep your cron jobs from trying to use the same resources.

Cron jobs are hidden building blocks for most of the websites. They are generally used to process/aggregate data in the background. However as a website starts to grow and there is gigabytes of data to be processed by every cron job, chances are that our cron jobs might overlap and possibly corrupt our data. In this blog post, I will demonstrate how can we avoid such overlaps by using simple locking techniques. I will also discuss a few edge cases we need to consider while using locks to avoid overlap.

He includes some sample code - both the class to create the functionality and a script showing how to make use of it (and, of course, an example of it in use).