603837 - Kraken: audio-beat-detection and audio-fft are quite similar

Status: RESOLVED WONTFIX

(Core :: JavaScript Engine, defect)

Description

[Nicholas Nethercote [inactive]]

FWIW, audio-fft and audio-beat-detection are almost the same benchmark.  
For example, they both spend roughly 50% of their time in the loop that begins
on line 334 of audio-{beat-detection,fft}.js.  Other hot loops look very
similar, eg. those on lines 153, 331, 309.

This isn't surprising when you realize that the lines 2--1918 of
audio-{beat-detection,fft}-data.js are identical.  audio-beat-detection is just
audio-fft with a tiny big of extra stuff at the end (about 2% of the runtime).  

There's a strong case to be made for removing one of the tests.  Alternatively, beat-detection should get a different data set, one that make the extra bit at the end much more important.

Comment 1

[Nicholas Nethercote [inactive]]

Hmm, they might not be quite as similar as I thought.  With bug 599914 fixed, the runtimes on my MacBook Pro are:

- audio-fft: 380ms
- audio-beat-detection: 578ms

There's still a lot of overlap, though.

Comment 2

[Nicholas Nethercote [inactive]]

Kraken is fading away. I don't think this needs to be open any more.