health site

Around 10 a.m. Monday morning, the Obama administration began using queuing software to meter entry into the Web site. At the time, the site had fewer than 40,000 users, somewhere in the "mid-30,000" range, as Medicare spokeswoman Julie Bataille put it.

"As we looked at error rates, that was the team's determination," Bataille said.

Most notably, the queuing system went up before hit its planned target of handling 50,000 concurrent users. When pressed on this point, Bataille referred to a separate metric that the administration has used to measure success: that 800,000 people be able to use the Web site in a single day.

"The idea is that we said the site would be able to handle 800,000 in the course of a day," Bataille said. "What we wanted to do today, with the new upgrades and to ensure the most optimal experience, was deploy the queuing that people would have the most optimal experience possible. We are working through this in real time."

With twice as much traffic as the site sees on a typical Monday, error rates and page wait times were higher than normal. By noon, the average page was taking two seconds to load. Web pages also had an error rate of 0.9 percent.