Flash Cards for Site Reliability Engineers

When Site Reliability Engineers architect systems they often use a method called Non-Abstract Large System Design (NALSD).

NALSD describes an iterative process for designing, assessing, and evaluating distributed systems. During the process it comes in handy to know some numbers about typical computing and data transferring tasks, such as locking a mutex or reading data from an SSD.

Jeff Dean even went so far to declare that everyone should know at least the most important numbers:


I, however, tend to forget these and all the other important numbers regularly. To train my forgetful brain I made myself some good old flash cards. I like to carry these with in my backpack and use them whenever I have to wait in line or public transport is late.

If you are interested in your own set of flash cards: Wait no longer! The Flash Cards for Site Reliability Engineers are just a slide deck because I found it easier to maintain.

Follow these easy steps to turn the slide deck into flash cards:

  • Print the document, preferably on thick paper
  • Fold each page once vertically, glue the back sides together
  • Cut out the cards along the black lines