One of my favorite pastimes over the last year or so has been to tear Twitter apart over uptime issues. See, for example, Twitter Suffers Minor Period Of Uptime (my personal favorite), Twitter: Something Is Technically Wrong and Amateur Hour Over At Twitter?.
Twitter has been mostly stable for the last month or so, though. And today cofounder Biz Stone wrote an email to Twitter users that says they’ve had 99.9% uptime over the last couple of months:
Reliability Update
Twitter has been making great progress in terms of uptime and reliability. Fail Whale sightings are far less frequent these days thanks to our efforts but we still have a long journey ahead. Last month we saw 99.88% uptime and so far this month we are at 99.96%. Our engineering and operations teams have been taking a very methodical approach to improving Twitter. We’re using the word “craftsmanship” to characterize our work here at the office. Reliability and dependability continue to be top on or list of key goals.
I’d say the email is tempting fate a little, but I’ve called Twitter on that same issue before and they failed to fail. Perhaps the worst of Twitter’s scalability issues are behind them (knocks on wood).