faster creation of PyList

[samuelcolvin]

No description provided.

[codspeed-hq]

CodSpeed Performance Report

Merging #74 will not alter performance

_{Comparing fast-pylist (6e80788) with main (f6b698e)}

Summary

✅ 59 untouched benchmarks

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 95.11%. Comparing base (37f9138) to head (6e80788).
Report is 60 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #74      +/-   ##
==========================================
- Coverage   96.59%   95.11%   -1.49%     
==========================================
  Files           9       10       +1     
  Lines        1294     1494     +200     
==========================================
+ Hits         1250     1421     +171     
- Misses         44       73      +29     

Files with missing lines	Coverage Δ
src/python.rs	97.18% <100.00%> (+0.26%)	⬆️

... and 5 files with indirect coverage changes

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[samuelcolvin]

This makes a substantial difference locally, but codspeed seems to disagree

???

[davidhewitt]

Is "locally" arm or x86_64? Might differ greatly between the two platforms.

TBH I'm ok with this but I also just think that really PyO3 should be reworking its list constructor to allow this.

[samuelcolvin]

Locally was macos.

[samuelcolvin]

Not clear there's an improvement on x86, might even be worse (although I have no idea how it could be):

So I'll leave this, we can either reconsider or close.

[davidhewitt]

I think better is that I aim to fix PyO3 to avoid needless reference count operations. Would be a modest speedup for quite a few operations / smaller binary size :)

[davidhewitt]

PyO3 0.23 (#137) has a new IntoPyObject trait which optimises transfer of reference counts, will close this.