2016-02-22 1:26 GMT-08:00 Tim Starling <tstarling(a)wikimedia.org>rg>:
I don't think it is plausible, given the data
collected at:
<https://meta.wikimedia.org/wiki/Research:HHVM_newcomer_engagement_experiment>
25,000 new users were put into an HHVM bucket, so the whole site was
twice as fast for them. Then they were tracked for a week. There was
no improvement in engagement or productivity.
I'm sure the performance improvements we did in 2004-2005 had a big
impact, especially initial batch of 9 Tampa servers in February 2004.
There must be a scale effect: going from 20s to 10s is much more
important than going from 2s to 1s.
I'm familiar with that research. I suggested at the time (see talk) to
specifically also evaluate impact on existing users. My reasoning was
that a new editor faces many barriers and high cognitive load, and as
you say, performance improvements at the level realized here are
probably not going to be the thing that helps you in making those
first edits. But if you're a power user who, say, performs a ton of
category edits with low cognitive load, reducing the amount of time
spent waiting ought to increase productivity.
Erik