Precompute Python Requirements Candidate Lookup#13656
Merged
notatallshaw merged 2 commits intopypa:mainfrom Nov 19, 2025
Merged
Precompute Python Requirements Candidate Lookup#13656notatallshaw merged 2 commits intopypa:mainfrom
notatallshaw merged 2 commits intopypa:mainfrom
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pfmoore
approved these changes
Nov 19, 2025
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In pathological backtracking this can end up being called millions of times.
With this change, in pathological scenarios, there is significantly less calling into packaging. Running one pathological example for example it goes from ~7.5 million Version objects being created to ~3.3 million Version objects being created. This is non-trivial and can be a ~20-25% saving in CPU time.
See the call graphs below:
Details
Before:
After: