Unless you've been living on a rock somewhere in space - and even then it'd have to be outside our galaxy - then you'll have heard the brain melting news that Gmail went offline earlier this week for a few hours. So what caused it?
Google has now gotten to the bottom of the issue:
"Lots of folks are asking what happened, so we thought you'd like an explanation," it explained today on its official blog. "This morning, there was a routine maintenance event in one of our European data centers. This typically causes no disruption because accounts are simply served out of another data center.
Unexpected side effects of some new code that tries to keep data geographically close to its owner caused another data center in Europe to become overloaded, and that caused cascading problems from one data center to another. It took us about an hour to get it all back under control.
The bugs have been found and fixed, and we're in the process of pushing out changes. We know how painful an outage like this is -- we run Google on Gmail, so outages like this affect us the same way they affect you. We always investigate the root causes of rare outages like this one, so we can prevent similar problems in the future."
In related news Google is also continuing its 2009 policy of continual Gmail tweaks with the expansion of its multiple inboxes functionality to now display numerous Gmail accounts, not just folders - a nifty move.
On top of this Google has sensibly switched the browser title of Gmail to display the number of new messages in your account first and foremost. This alteration can be added through the Labs tab and is far more easily explained by the picture below...