Pipelining optimization technique boosts speed and availability, Keynote says.
Bill Siwicki , Managing Editor, Mobile Commerce
Foot Locker climbed 26 spots to hit No.1 on the Keynote Mobile Commerce Performance Index for the week ending Oct. 21. One of the keys to its success was instituting a performance optimization technique known as pipelining, where multiple server requests are made within the same call as opposed to handling requests one by one, waiting for a response to one request before making another, says mobile and web performance management firm Keynote Systems Inc.
“This is the first time Foot Locker has made it to the top five on the index. A site that has 24 elements on the home page and a page size of 210 kilobytes made it to the top of the index, which is surprising,” says Venkatesh Giri, mobile performance expert at Keynote Systems, of the relatively high numbers. “Last week we observed Foot Locker dropped in ranking due to availability issues across multiple carriers and multiple locations creating timeout and other random errors. This week they outperformed all the retail sites in this regard, maintaining a consistent availability across all locations and all carriers.”
Maintaining consistent mobile commerce site availability across carriers is a huge challenge because mobile networks have a much higher latency on average than wired networks, causing timeout and connection errors, Giri says.
Foot Locker’s m-commerce site home page loaded on average in 8.77 seconds and did so completely and successfully 100% of the time, Keynote finds. The weighted and combined load time and success rate earned Foot Locker an index score of 937 out of 1,000.
“Foot Locker used explicit ‘Connection: Keep-Alive’ headers for all their objects on the home page,” Giri explains. “’Keep Alive’ is used to keep the connection open to make the subsequent requests faster and it is also used to leverage HTTP pipelining on supporting mobile web browsers. HTTP pipelining is a performance optimization technique where the browser may send multiple HTTP requests to the server on the same connection without waiting for subsequent responses, thus improving round trip time overhead for all elements after the first byte has been downloaded.”
Foot Locker, No. 23 in the Internet Retailer Mobile 400, did not immediately respond to a request for comment.
Barnes & Noble came in second for the week ending Oct. 21 with a load time of 5.44 seconds and a success rate of 99.78% for a score of 930. And HSN Inc. tied for second with a load time of 5.40 seconds and a success rate of 99.78% for a score of 930.
The average load time for all 30 retailers on the index was 8.57 seconds, the average success rate was 99.17% and the average score was 771.
Click here and then click on Keynote Mobile Commerce Performance Index Part 1 and Part 2 to see this week’s complete results for all 30 retailers on the index.
Keynote Systems measures 30 representative m-commerce sites exclusively for Internet Retailer. The sites include merchants in multiple categories and channels, and of multiple sizes, ranging from such giants as Amazon.com Inc. to midsized retailers like Toolfetch.com LLC. Amazon is No. 1 in the Internet Retailer Mobile 400, Toolfetch.com is No. 248. Keynote tests the sites in the index every hour Monday through Sunday from 8 a.m. through midnight Eastern time, emulating three different smartphones on three different wireless networks: Apple Inc.’s iPhone 4 on AT&T, the HTC Evo on Sprint and the Droid X on Verizon. The HTC Evo and the Droid X run Google Inc.’s Android operating system. Keynote runs the tests in New York and San Francisco.
Keynote combines a site’s load time and success rate, equally weighted, into a single score. Given that both performance and availability are important, the score reflects the overall quality of the home page; a higher score indicates better performance. Scores also reflect how close sites are to one another in overall quality. The index average score is the midpoint among all the sites’ scores.