Trouble Using Twitter Yesterday? Blame a “Cascading Bug”
If using Twitter yesterday felt a little bit like the Fail Whale days of yore, you weren’t alone: A major technical issue caused Twitter to be unavailable worldwide for over an hour yesterday. The issue has since been resolved, but it’s an embarrassing moment for a company that boasts 99.99% uptime in the last six months.
Users who have been with Twitter for years will remember the over capacity “Fail Whale” error message that used to grace the site all too often. However, over capacity issues were largely worked out as Twitter expanded, and recently the Fail Whale has all but vanished. In fact, yesterday’s issues were caused by something completely different.
Twitter’s VP for engineering Mazen Rawashdeh explains that it was a “cascading bug” that brought the service to its knees. From Twitter:
This wasn’t due to a hack or our new office or Euro 2012 or GIF avatars, as some have speculated today. A “cascading bug” is a bug with an effect that isn’t confined to a particular software element, but rather its effect “cascades” into other elements as well. One of the characteristics of such a bug is that it can have a significant impact on all users, worldwide, which was the case today. As soon as we discovered it, we took corrective actions, which included rolling back to a previous stable version of Twitter.
Back in the early days, Twitter’s constant downtime and other idiosyncrasies were almost part of the fun. Not only did we have Fail Whales in those days, but Tweet Jails well — for when you pushed out too many messages in rapid succession. However, Twitter is not the company it used to be and, as All Things D points out, they have a lot more on the line:
But Twitter has scaled over the past six years from an easily dismissed Silicon Valley plaything to the next most-anticipated technology company IPO. It is currently in the midst of a major internal reorganization, the blueprints of which come straight from the top. And ever expanding, the company was forced to move offices just recently, as its headcount ballooned from the low hundreds to close to 1,000 over the past year.
In addition to large scale personel, technical, and HQ expansions, Twitter has worked to start making money as well. A recent deal with NASCAR touted a new way for advertisers to use Twitter, but yesterday’s episode could give potential advertisers pause for thought.
Twitter is no doubt painfully aware of their tenuous situation, and while yesterday’s (admittedly brief) downtime was just a technical headache, if it keeps happening the company will have far bigger problems than cascading bugs.