GMail is back from unexpected downtime.

EDIT: Updated. Read on to find out more.
Sorry for the lateness about this news article, it’d seem that no one was around to cover it. GMail, Google‘s mail application, was down for most of today. No one was quite sure on exactly what caused the downtime — apparently not even Google, at the time. Google posted something on their blog roughly two hours ago; although they do not specify what caused the downtime.

“We know many of you are having trouble accessing Gmail right now — we are too, and we definitely feel your pain. We don’t usually post about minor issues here (the Apps status dashboard and the Gmail Help Center are usually where this kind of information goes). Because this is impacting so many of you, we wanted to let you know we’re currently looking into the issue and hope to have more info to share here shortly. If you have IMAP or POP set up already, you should be able to access your mail that way in the meantime. We’re terribly sorry for the inconvenience and will get Gmail back up and running as soon as possible.” – Google Blog

We’re not actually sure on what caused the downtime, but as soon as we know, this post will be updated. Google will most likely update their blog, anyway.

Edit: And they did; here’s a portion of their side of the story, more of which can be read on the actual blog post.

“Here’s what happened: This morning (Pacific Time) we took a small fraction of Gmail’s servers offline to perform routine upgrades. This isn’t in itself a problem — we do this all the time, and Gmail’s web interface runs in many locations and just sends traffic to other locations when one is offline.

“However, as we now know, we had slightly underestimated the load which some recent changes (ironically, some designed to improve service availability) placed on the request routers — servers which direct web queries to the appropriate Gmail server for response. At about 12:30 pm Pacific a few of the request routers became overloaded and in effect told the rest of the system “stop sending us traffic, we’re too slow!”. This transferred the load onto the remaining request routers, causing a few more of them to also become overloaded, and within minutes nearly all of the request routers were overloaded. As a result, people couldn’t access Gmail via the web interface because their requests couldn’t be routed to a Gmail server. IMAP/POP access and mail processing continued to work normally because these requests don’t use the same routers.”  – Google Blog

So, looks like it was a simple maintenance gone wrong. Aye up, google.