DOC: parallel safe

[TomAugspurger]

@datapythonista this may have been why the parallel option wasn't helping you.

[codecov]

Codecov Report

Merging #24638 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #24638   +/-   ##
=======================================
  Coverage   92.37%   92.37%           
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  Files         166      166           
  Lines       52388    52388           
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  Hits        48396    48396           
  Misses       3992     3992

Flag	Coverage Δ
#multiple	90.8% <ø> (ø)	⬆️
#single	43% <ø> (ø)	⬆️

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[codecov]

Codecov Report

Merging #24638 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #24638   +/-   ##
=======================================
  Coverage   92.37%   92.37%           
=======================================
  Files         166      166           
  Lines       52388    52388           
=======================================
  Hits        48396    48396           
  Misses       3992     3992

Flag	Coverage Δ
#multiple	90.8% <ø> (ø)	⬆️
#single	43% <ø> (ø)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 510afa7...b2efc64. Read the comment docs.

[jreback]

lgtm. will merge shortly.

[jreback]

thanks!

[datapythonista]

I built the documentation with 4 jobs on master now, and took 5m30s (was 17m30s before). It's working as expected now, thanks!

Not sure if there is something similar for python setup.py build_ext. It also ignores the -j option for me, and doesn't parallelize.