fixes performance regression with AR relations#34503
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gingerlime wants to merge 1 commit intorails:masterfrom
Closed
fixes performance regression with AR relations#34503gingerlime wants to merge 1 commit intorails:masterfrom
gingerlime wants to merge 1 commit intorails:masterfrom
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* After introducing cache versioning, even with cache versioning off there's a performance regression when passing an Active Record relation to cache * This happens in ActiveSupport::Cache inside `normalize_version` * This method would check if the relation responds to cache_version and if not, would recrusively normalize it with `to_a` * This would lead to the relation being retrieved from database and enumerated, causing the performance regression * This fix simply adds `cache_version` returning `nil` to Active Record relations * This is a temporary stopgap, until relation cache versioning is implemented. See rails#34378
Member
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Thank you for the PR. We prefer to not implement stopgap solutions in the codebase. Let's wait for #34378 |
Contributor
Author
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This bug can cause quite severe performance regression from my experience, and it largely goes unnoticed, unless you actively measure performance. Hope that #34378 gets merged quickly and also backported, to fix existing versions of rails affected by this regression. |
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there's a performance regression when passing an Active Record
relation to cache
normalize_versionand if not, would recrusively normalize it with
to_aenumerated, causing the performance regression
cache_versionreturningnilto Active Recordrelations
implemented. See collection cache versioning #34378