buildifier: improve Windows runner performance#1404
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### What does this PR do? Apply a last path on `buildifier`'s runner script template on Windows: - bazelbuild/buildtools#1404 ### Motivation Decrease execution time from [~2 minutes](https://gitlab.ddbuild.io/DataDog/datadog-agent/-/jobs/1177131952#L77) to [~2 seconds](https://gitlab.ddbuild.io/DataDog/datadog-agent/-/jobs/1180039154#L99). ### Describe how you validated your changes Locally (Windows VM) and in CI (1985f7f). ### Additional Notes Closes [ABLD-174](https://datadoghq.atlassian.net/browse/ABLD-174). [ABLD-174]: https://datadoghq.atlassian.net/browse/ABLD-174?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ
AnnaSvalova
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Nov 6, 2025
| $i = 0;^ | ||
| while ($i -lt $Files.Count)^ | ||
| {^ | ||
| $Batch = $Files[$i..($i + 99)];^ |
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LGTM, but could you add a comment here please? About Windows' command line length limitation and 100 files.
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@AnnaSvalova Done in 2nd commit (f5fad4e).
This change aims to improve the `buildidier`'s runner performance on Windows where it can sometimes take minutes to complete. It consists in replacing the slow COM `Scripting.FileSystemObject` with a "native" PowerShell `Get-ChildItem -Recurse` for file discovery, and batch `buildifier` invocations (100 files at a time) instead of invoking once per file. This improves performance on large codebases (like from about 2 minutes to less than 3 seconds). Notes: - cross-process COM calls add latency, whereas `Get-ChildItem` is a compiled "cmdlet". - by default, `Get-ChildItem` doesn't recurse into symbolic links to directories, which is consistent with the current implementation that explicitly avoids entering `ReparsePoint`s, - batching files passed to `buildifier` reduces process creation overhead, with a limit to account for Windows command line length limitations.
This is to address following review comment: > LGTM, but could you add a comment here please? About Windows' command > line length limitation and 100 files. (bazelbuild#1404 (comment)) References: - https://stackoverflow.com/questions/73893997/comments-in-a-long-line-powershell-code-in-a-batch-script - https://stackoverflow.com/questions/3205027/maximum-length-of-command-line-string - https://devblogs.microsoft.com/oldnewthing/20031210-00/?p=41553
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This change aims to improve the
buildidier's runner performance on Windows where it can sometimes take minutes to complete.It consists in replacing the slow COM
Scripting.FileSystemObjectwith a "native" PowerShellGet-ChildItem -Recursefor file discovery, and batchbuildifierinvocations (100 files at a time) instead of invoking once per file.This improves performance on large codebases (like from about 2 minutes to less than 3 seconds).
Notes:
Get-ChildItemis a compiled "cmdlet",Get-ChildItemdoesn't recurse into symbolic links to directories, which is consistent with the current implementation that explicitly avoids enteringReparsePoints,buildifierreduces process creation overhead, with a limit to account for Windows command line length limitations.