I was talking to someone on the phone yesterday about insurance and he needed to send me a PDf file as proof. I told him just send it to my Gmail account, and then remembered, last time I'd looked Gmail was down.

The guy said, "Well, I'm sure it's back now. It wouldn't be down for more than a few seconds. It's Gmail!"

Well, it was down for about two hours on Tuesday.

On the Gmail blog, as related by TechCrunch, the VP Engineering for Google explained:

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. 

Oopsee.

I use Gmail, Google Calendar, Reader, Docs ... tons of stuff. Love it. But none of it is mission critical. I back up some docs locally that I need to get at on demand, just in case.

There are arguments that digital signage already uses so-called cloud computing through SaaS services that do the hosting for DS networks. But the more precise definition for cloud computing is that of facilities and services that host applications that scale up or down on demand, can handle huge volume, and never go down. SaaS services uses cloud computing services as hosts.

Well, Gmail is in the cloud and it went down. MOST DS platforms use forward and store routines that mean even when there is something wrong centrally, or broadband is out, the players will merrily play what they have stored locally until new updates arrive. So something wrong in the server cloud is not all that big a deal.

But if your service hangs its hat on persistent, dynamic updates, then you want to make sure whatever you set up has some fail-over, meaning a technical Plan B, to keep the updates coming. If Gmail can go down, that suggests pretty much anything can go down. I would not see this as a serious concern, but a reminder that nothing is infallible.