Reduce allocations when matching composite globs by davkean · Pull Request #15006 · dotnet/msbuild

davkean · 2026-09-11T14:50:40Z

Matching a filename against composite include/exclude globs repeatedly allocates normalized copies of the same path. Reuse normalization for consecutive globs with the same root during a single match, without retaining filenames between calls. Preserve matching order, short-circuiting, and custom IMSBuildGlob implementations.

Allocation-stack comparison for the Visual Studio OrchardCore build workload, using the original PR revision 0d7bea47 against baseline d257108c:

Allocation stacks	Baseline (MB)	Changed build (MB)	Reduction
Glob path normalization	132.7	40.6	69%
Glob matching, including children	157.1	63.2	60%

Reuse normalized input for consecutive include and exclude globs with identical roots within one match. Keep custom matcher dispatch and short-circuiting unchanged, without retaining paths between calls. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 8013ed0f-9ede-4eb7-a35b-835c87d73e76

davkean commented Sep 11, 2026

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Comment thread src/Build/Globbing/CompositeGlob.cs

davkean commented Sep 11, 2026

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Comment thread src/Build/Globbing/GlobMatchContext.cs Outdated

davkean force-pushed the dev/davkean/reuse-glob-match-normalization branch from 0d7bea4 to b2dbe57 Compare September 12, 2026 00:21