> On 13 Apr 2016, at 4:22 PM, Ryosuke Niwa <[email protected]> wrote:
>
> I don’t think order of magnitudes tests ever quite worked JSC (it was added 
> by Google so it obviously worked on V8).  If adjusting the threshold was all 
> that was needed to make the tests pass, I see no reason how to change it.

Adjusting the threshold is one part, but we’re also improving the method by 
examining the slope to give a better indication of whether the test is running 
in constant time.

>
> However, what you proposed will only reduce the likelihood of type I errors 
> (false positives).  You should also examine how it affects the likelihood of 
> type II errors (false negative).  You might want to make some API 
> artificially O(n^2) and make sure the test starts failing, etc…

That’s a fair comment (regarding false negatives), we can do that. But to be 
honest, I don’t have a lot of faith in the reliability of these tests anyway. 
Since they were added by Google, do you have any thoughts on whether we could 
remove them?

> You can probably look at the svn/git blame the change which added relevant 
> tests in LayoutTests/perf/ and apply a reverse change locally to test that.

Sorry, I’m not following what you’re saying here.


Nikos
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