Twitter Stalls - Again

Events such as the World Cup have caused increased activity on the site, and Twitter said this, combined with system enhancements and upgrades, have uncovered networking issues. "As we go through this process, we have uncovered unexpected deeper issues and have even caused inadvertent downtime as a result of our attempts to make changes,” Twitter said Tuesday in a company blog.

Twitter added, “Ultimately, the changes that we are making now will make Twitter much more reliable in the future. However, we certainly are not happy about the disruptions that we have faced and even caused this week and understand how they negatively impact our users.

The company said it will double the capacity of its internal network, improve network monitoring and rebalance traffic on its internal network.

On Monday, Twitter experienced problems that lasted for several hours, resulting from “the failed enhancement of a new approach to timeline caching.” Later it said that users “may temporarily experience missing tweets from their timelines,” and, later, that Twitter was “recovering from the site outage.”

Last week, Twitter.com and its platform for third-party applications also were down several times. Twitter, in a detailed June 11 posting on its engineering site, blamed “several incidences of poor site performance and a high number of errors due to one of our internal sub-networks being over-capacity.”

The posting provided details about the causes of the disruptions and what the company was doing to fix them, including doubling the capacity of its internal network, improving network monitoring, and “rebalancing traffic” on the internal network to redistribute the load.

Since its launch in March 2006, Twitter has experienced its ups and downs in terms of site availability. According to Website monitor Pingdom, Twitter has maintained an uptime of 99 percent or higher since July 2008. So far in June, the time has dropped to 98.54 percent.

Pingdom also accounted for Twitter’s five hours of downtime this month. The longest outage was recorded in October 2009, when it went out for five hours and 16 minutes.

When the site stalls, it directly affects not only private individuals who constantly update their status via 140-character updates, but also businesses that rely on “Promoted Tweets” for real-time updates. Twitter is reportedly talking with Microsoft and Google to streamline its search functionality.