He suggested that a lack of oversight of the whole website development, automation processes and time may have led to developers downloading what they needed without checking first if had already been downloaded elsewhere, therefore missing the opportunities to merge files.
As well as merging, files could have been 'minified', Grabner said.
"Let's take a look at one particular file - jQuery.DataTables.js - with a size of 440KB," he illustrated in his blog.
"Putting it through a public available minifier such as jscompress.com reduces the file size to 83KB - that's a reduction of more than 80 percent!"
Continued performance monitoring
Grabner is continuing to monitor the performance of Healthcare.gov and has created a web page to map the results.
The performance map highlights the US states that experience an average response time of more than eight seconds in red, and green for four seconds or less.
There are two possible explanations for the longer response times, Grabner said. One is that the broadband connectivity of the states might not be as good.
However, Grabner suggested Healthcare.gov might be responsible for the second reason.
"It could be they don't leverage CDN (content delivery network) services," he said. "[CDN would allow them to] distribute the content geographically local to the end user [rather than sending the data from servers based thousands of miles away]."
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