Yesterday, we pushed out Socorro 2.1, which changes the way we calculate crashes/ADU. We’ve now started including content and plugin crashes in these crash counts. This means that when you look at graphs on crash-stats.mozilla.com today, you’ll see an uptick in crashes. This is not a “crash spike” but a change in the way we represent the data, as requested by the CrashKill team.

To give some background, the crashes/ADU metric counts the number of crashes per 100 average daily users. It’s often used as a metric for stability of releases.

In version 2.2, which we are working on at the moment, we’ll be changing the way we aggregate data for beta and release versions. Right now, as an artifact of pre-rapid-release days, all beta crashes are counted under the same version regardless of whether it’s beta 1, beta 7, etc. This is turning out to be quite challenging to build when you realize that a build (and hence crash reports from a build) doesn’t know which beta it is.

My colleague Robert Kaiser has blogged about these changes more extensively, focusing in particular on what this means for data interpretation. He’s written a fantastic blog post – please jump on over there and read it for a lot more context.