Tuning AFT parameters

[shanti]

I'm playing around with the AFT measurement without much success. I am unable to get it produce any values. I've experimented with different pixel counts - going from 5 - 500. I've also tried cutoff times up to 60 seconds.

Here is an example test result:
http://www.webpagetest.org/result/110824_JF_1DFJ0/

All help appreciated
Shanti

[pmeenan]

If you go to the screen shot page there is a diagnostic image for the AFT measurement: http://www.webpagetest.org/result/110824...reen_shot/ that shows how the various pixels on the page were tagged.

The "late static" pixels are the ones that prevent the AFT algorithm from being confident about a result.