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Tool Perf Regression

Category: Performance · Tier: All

Detect performance regression against a baseline. Uses dual thresholds: both percentage AND absolute change must be exceeded.

Profiles: strict (perf envs, FCP 10%/50ms), normal (default, FCP 20%/100ms), ci (pipelines, FCP 25%/150ms), lenient (dev, FCP 30%/200ms).

When to Use

Compare current metrics against stored baselines. Detect regressions across deploys.

Parameters

Parameter Type Required Description
url string Yes URL to test
baselineName string Yes Name of baseline to compare against
sensitivity string No Sensitivity profile: strict (perf testing), normal (local dev), ci (automated pipelines), lenient (development)
thresholdLcp number No Override LCP threshold percentage

Example

Check if the latest deploy slowed down any pages

Tips

  • Combine with other tools for full analysis

Research

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