What's a reasonnable time to run dokka on ~30k lin...

# dokka

[mbonnin]

What's a reasonnable time to run dokka on ~30k lines of kotlin ? It currently takes ~30min on my machine and ~1h in CI, that looks very long. Or is that standard times ?

[simon.vergauwen]

That sounds quite slow indeed. We have dokka set up in Arrow I can run it to compare if you like.

[mbonnin]

Other datapoints would be great

[simon.vergauwen]

Cloc result. I am running dokka now

Untitled

[mbonnin]

On my side:

-------------------------------------------------------------------------------
Language                     files          blank        comment           code
-------------------------------------------------------------------------------
Kotlin                         414           6294           2489          29390
XML                            314           1243            231          21194
JSON                             1              0              0            104

I'm using the gradle plugin on an Android module. I have one CPU core running 100%.

[simon.vergauwen]

I have 5 CPUs jumping to 80%+ immediately lol

[simon.vergauwen]

6*

[simon.vergauwen]

First try I ran into a dokka bug 😅 We run into this frequently and requires a CI rebuild.

[simon.vergauwen]

Untitled

Untitled

[mbonnin]

Interesting.... Updating to 0.9.18 (was 0.9.17 before) allows dokka to grab > 400+% CPU. But it then fails with org.jetbrains.kotlin.asJava.builder.ClsWrapperStubPsiFactory$1 cannot be cast to com.intellij.psi.PsiJavaFile

[mbonnin]

which is this bug: https://github.com/Kotlin/dokka/issues/455

[mbonnin]

Tried running a profiler and it looks like ~47% of the time is spent in GCTaskThread::run, 16% in CompileBroker and "only" 34% in DokkaGenerator.generate...

[simon.vergauwen]

What command did you run for that info?

[mbonnin]

Screenshot at 2019-10-02 16-39-51.png

[mbonnin]

Comes from the intellij profiler: https://www.jetbrains.com/help/idea/cpu-profiler.html

[mbonnin]

I attached it during 30s while the gradle task was running

[mbonnin]

Turns out, applying the dokka-android plugin instead of plain dokka does the trick. I'm down to ~3-4min which is way more acceptable. Still a bit long for 30k loc IMO but that'll do for now.

[mbonnin]

ah, maybe not, I also changed the outputFormat...

[simon.vergauwen]

I am having a hard time testing it. It fails very frequently locally :s A dokka internal Guice reflection bug 😞

[simon.vergauwen]

Ah yeah, I am sure dokka-android is heavy but not sure if that’s related to dokka or the Android’s heavy classpath.

[mbonnin]

😕

[simon.vergauwen]

I’m down to ~3-4min

That sounds much more in line with what I see on the Arrow repo considering the difference in size of project.

[mbonnin]

So looks like it was more outputFormat = "javadoc" in the end...

[mbonnin]

I added it again and I'm bad to > 5min build (I just aborted it).

[mbonnin]

The Edit-Compile-Run cycle is quite long 😅

[simon.vergauwen]

We have a rather funky setup. We have jekkyl as outputFormat. Which we then run another custom tool over it and we modify the output and build our website from it 😄

[mbonnin]

Maybe it's that issue: https://stackoverflow.com/questions/41189284/is-there-a-way-to-speed-up-javadoc-takes-7-minutes

[simon.vergauwen]

This currently takes 7 min or 6 files per second.

😱

[mbonnin]

¯\_(ツ)_/¯

[mbonnin]

I'll open an issue for tracking

[simon.vergauwen]

Painful. Writing documentation is hard enough by itself