Almost 150,000 Gmail users on Sunday could not find their e-mail messages or had trouble accessing the service, prompting cries for help on Google's support forum.
Google acknowledged the service problem through the Google Apps dashboard shortly after noon PST on Sunday.
After several status updates, Google initially said that 0.29% of users had been affected. The company then revised that figure to 0.08% of users.
Google's Gmail service is one of the most popular in the world, with an estimated 170 million users worldwide. Based on these figures, which Google has not specifically confirmed, about 136,000 users are affected.
Other reports put the number closer to 150,000. Google did not immediately respond to a request to clarify these figures. Nor did the company respond to a query about whether any paying business customers were affected or whether any credit will be granted to business customers per the terms of the company's service level agreement (SLA).
In January, Google said that it was striving to make Google Apps as reliable as telephone dial-tone and amended its SLA to eliminate planned downtime as an allowable exemption to its SLA guarantee. By making this commitment, Google was effectively claiming that its service is more reliable than competitors, which have to plan for downtime maintenance to keep their systems running.
On Monday, Google confirmed that it has yet to resolve the problems affecting Gmail.
"Yesterday a very small number users started having difficulty accessing their Gmail accounts, and in some cases once they got in, trouble viewing e-mails," a company spokesperson said in an e-mailed statement. "This is affecting less than 0.08% of our Gmail user base, and we've already fixed the problem for some individuals. Our engineers are working as quickly as possible and we hope to have everything back to normal soon. We're very sorry for the inconvenience to our customers."
Gmail had a fairly good year last year in terms of availability. Service was a bit more uneven in 2009.
The missing e-mail messages are likely to be recovered, as they already have been for some users. Google maintains a lot of redundancy in its systems. But not being able to access years of messages is disconcerting. For some users, the outage is making them question their faith in the cloud computing model.
"Well--what if the cloud fails?" asks a user posting under the name "jjewel." "If, ultimately, Google does not make this right in a timely way and I lose the main record of the last seven years of my life ...that will forever affect how I view trusting an anonymous server farm somewhere with my critical or even not-so-critical data. I imagine it's the same with all of you."
Update: Google, about 11am Pacific Time, revised downward the number of Gmail users believed to have been affected. Using the estimated Gmail user base of 170 million, the amended figure would be something like 34,000.
"We actually now have a better understanding of the impact of this issue, and we have lowered our estimate of the number of affected Gmail users from 0.08% to 0.02%," a company spokesperson said in an e-mail. "We have restored access for a third of those affected. The remaining 0.013% of accounts are being restored on an ongoing basis, and we expect the issue to be resolved for everyone within 12 hours."