Re: Add a cooperative FS lock to lilypond-book. (issue 555360043 by address@hidden)

[jonas . hahnfeld]

So I can see a consistent improvement by ~40s for 'make -j4 CPU_COUNT=4
test', going down from ~4m to 3m30s. The patch at
https://codereview.appspot.com/547680043 explains that this is due to
parallelism in input/regression/lilypond-book/. I see no influence on
'make -j4 CPU_COUNT=4 doc', staying flat at around 29m on my laptop.

If only looking at input/regression/lilypond-book/, can't we just use
different 'lily_output_dir's for each target? That should still allow us
to run in parallel without the locking solution proposed in this patch.
Correct me if I'm wrong: This should have no negative influence since
files from input/regression/lilypond-book/ are not reused in other parts
of the tests / documentation.
Another solution might be serialize only lilypond-book and let tex et
al. run concurrently. That should also be harmless, right?

In total I'm still not convinced by this complexity.

https://codereview.appspot.com/555360043/