React Profiler long render duration: causes and next steps?
Tests interpreting actualDuration vs baseDuration. Outline: close values on updates mean broken memoization—add memo or useMemo; high baseDuration alone means an inherently slow subtree. Red flag: proposing fixes before comparing these two Profiler metrics.
Tests whether you interpret Profiler metrics diagnostically by comparing actualDuration to baseDuration. Outline: first, check if actualDuration nearly equals baseDuration during updates—this signals memoization is not working, so apply memo or useMemo; second, if baseDuration itself is high even when actualDuration is low, the subtree is inherently expensive to render and needs simplification; third, note the phase to distinguish mount costs from update regressions.
Read the original → react.dev
- #react
- #profiler
- #performance
- #memoization
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