render: avoid deepcopying

[skshetry]

A low hanging fruit that reduces 20% of runtime when run in vscode-dvc-demo with:

dvc plots diff $(git log --oneline --pretty=format:"%h")

[codecov]

Codecov Report

Base: 93.07% // Head: 93.06% // Decreases project coverage by -0.02% ⚠️

Coverage data is based on head (c417478) compared to base (6f87c14).
Patch coverage: 100.00% of modified lines in pull request are covered.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #9033      +/-   ##
==========================================
- Coverage   93.07%   93.06%   -0.02%     
==========================================
  Files         456      456              
  Lines       36814    36758      -56     
  Branches     5335     5324      -11     
==========================================
- Hits        34264    34207      -57     
- Misses       2025     2026       +1     
  Partials      525      525              

Impacted Files	Coverage Δ
dvc/render/convert.py	87.09% <100.00%> (-0.41%)	⬇️
dvc/render/converter/vega.py	91.20% <100.00%> (-0.05%)	⬇️
dvc/repo/diff.py	95.31% <0.00%> (-3.00%)	⬇️
dvc/output.py	89.18% <0.00%> (-0.30%)	⬇️
tests/func/test_diff.py	100.00% <0.00%> (ø)
dvc/repo/index.py	89.88% <0.00%> (+0.57%)	⬆️

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[daavoo]

This is clearly another low-hanging fruit:

https://github.com/iterative/dvc-render/blob/2aa47c86a4a364b0d410e90671b6e57de045b9d7/src/dvc_render/vega_templates.py#L66-L71

Goes back to iterative/dvc-render#23 / iterative/dvc-render#28 (not treating the template content as string)

[skshetry]

This is clearly another low-hanging fruit:

iterative/dvc-render@2aa47c8/src/dvc_render/vega_templates.py#L66-L71

Goes back to iterative/dvc-render#23 / iterative/dvc-render#28 (not treating the template content as string)

Thanks for the links. Seems a bit involved though, right? Does that keep backward-compatibility?

[daavoo]

This is clearly another low-hanging fruit:
iterative/dvc-render@2aa47c8/src/dvc_render/vega_templates.py#L66-L71
Goes back to iterative/dvc-render#23 / iterative/dvc-render#28 (not treating the template content as string)

Thanks for the links. Seems a bit involved though, right?

I can give it a quick try as I have recently looked at it.

Does that keep backward-compatibility?

It should as there are internal operations, I/O should remain the same

[skshetry]

Thank you. FYI I ran the above benchmark with dvc pull --all-commits, so the collect() is not very pronounced.