E-retailer eBags.com had a record-setting holiday season last year, in which its sales increased 32% year over year. A large part of that success was due to the site performance monitoring and load testing that it did with Keynote Systems Inc., says Mike Frazzini, eBags.com vice president of technical operations.

“We were able to leverage Keynote’s services to ensure we could handle our record 2011 holiday season and Cyber Monday with great performance,” says Frazzini. On the Monday following Thanksgiving, also known as Cyber Monday, the retailer’s sales increased 46% over 2010’s tally. EBags declined to disclose total sales figures.

EBags, No. 114 in the Internet Retailer Top 500 Guide and No. 101 in the Mobile Commerce Top 300, also said that 13.4% of visits to its site came from mobile devices this past holiday season, up from 5.8% the year prior. EBags began working with Keynote in April 2011.

The performance monitoring and external load testing service highlighted areas that needed improvement, thereby contributing to the retailer shaving one second from the eBags e-commerce home page load time and two to three seconds from other pages, Frazzini says. “It pinpoints performance issues and lets us take corrective action internally and with our third-party providers.”

The Keynote service employs more than 20 browser, transaction and application monitors that provide alerts and reports on any performance and availability criteria across 20 major metropolitan areas.

Having such an extensive monitoring program enables eBags to continuously track such internal performance-related areas as application development and graphic design, as well as third-party elements like marketing beacons that can impact site performance, Frazzini says.