I’m starting this thread here, prompted by @carltongibson mentioning it in this thread about a formatter for CSS and JS in Django:
There was an aside about clever things you can do to reduce time in CI, that has been pioneered by the folks at Mozilla working on the Firefox browser.
I’ll share the quote from Carlton, which was quoting an earlier convo between us before about optimising CI time:
The best example I know in the public domain is the work Mozilla did when they looked at recoding the time spent in CI on their machine,
Testing Firefox more efficiently with machine learning - Mozilla Hacks - the Web developer blog
Mozilla found something like a 99% percent saving in CI time, when they started using a model to see which tests it might make sense to run when a new patch was introduced. Here’s a choice quote about the approach they have been taking and the newer approach they were experimenting with in 2020:
His response:
That “something like a 99% percent saving in CI time” result is frankly eye-watering. A 99% percent saving — if we could get even some of that.
I’ve started this thread to dump some links and notes, as it’s a thing I’ve been looking into more of late.
More to come later.