Following on from last months Google Search problems, users of Google's popular e-mail service, Gmail, were hit by an outage yesterday. The service went offline at 0930 GMT with Google saying it was "working hard to resolve this problem". The problem covered both their general consumers and the paid for business users. Professional users of Google mail are covered by a service level agreement that promises to be 99.9% operational in any calendar month. To put that commitment in context, GMail could be down up to 72 hours per month and still meet their commitments! Most commercial email services are run on 99.999% or 5 nines availablity or just 72 minutes of unplanned downtime per month.
According to comScore there are more that 113 million users of Google’s “GMail” service worldwide. In a statement, Google said "a number of users" were having problems with Google Mail. The problem wasn’t universal with some users unaware of the problems. Users accessing GMail through a third-party email clients configured to send and receive e-mail using the IMAP email protocol were unaffected.
Outages are nothing new to email services and all Google’s competitors have had similar experiences as they developed and certainly Google has invested significantly in their Gmail infrastructure. According to Google, its e-mail service suffered an average of 10 to 15 minutes of downtime per month in 2008. The last major outage was in August 2008 when users were unable to use Google Mail for "a couple of hours".
According to comScore, Google has the world's third most popular web mail service behind Hotmail with 283 million users and Yahoo with 274 million e-mail users.
Google will need to improve their target availability if they are to offer the GMail service as a credible alternative to competitive email services.
