• Jackson Gardner's avatar
    Improve web benchmarks measurements (#127900) · e8f4d803
    Jackson Gardner authored
    By default, the browser fuzzes the timer APIs such that they have a granularity of approximately 100 microseconds (this is due to Spectre mitigation techniques). However, many of the thing we are trying to measure actually have a much finer granularity than 100 microseconds. As a result, many of our benchmarks are extremely noisy and don't provide accurate data.
    
    By serving the initial script files with the `Cross-Origin-Opener-Policy: same-origin` and `Cross-Origin-Embedder-Policy: require-corp` HTTP headers, the browser runs the benchmarks in a `crossOriginIsolated` context, which restores the fine granularity of APIs such as `performance.now()` to microsecond precision.
    
    Also, we were considering anything an outlier that was more than one standard deviation away from the mean. In a normal distribution, that means we are only capturing 68% of the data and the rest are considered outliers. This is not ideal. Doing two standard deviations away captures 95% of the data, and the outliers are in the remaining 5%, which seems much more reasonable.
    e8f4d803
Name
Last commit
Last update
.github Loading commit data...
.vscode Loading commit data...
bin Loading commit data...
dev Loading commit data...
examples Loading commit data...
packages Loading commit data...
.ci.yaml Loading commit data...
.cirrus.yml Loading commit data...
.gitattributes Loading commit data...
.gitignore Loading commit data...
AUTHORS Loading commit data...
CODEOWNERS Loading commit data...
CODE_OF_CONDUCT.md Loading commit data...
CONTRIBUTING.md Loading commit data...
LICENSE Loading commit data...
PATENT_GRANT Loading commit data...
README.md Loading commit data...
TESTOWNERS Loading commit data...
analysis_options.yaml Loading commit data...
dartdoc_options.yaml Loading commit data...
flutter_console.bat Loading commit data...