TaskHost IBuildEngine Callback Support spec#12868
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JanProvaznik wants to merge 8 commits intodotnet:mainfrom
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TaskHost IBuildEngine Callback Support spec#12868JanProvaznik wants to merge 8 commits intodotnet:mainfrom
JanProvaznik wants to merge 8 commits intodotnet:mainfrom
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looks pretty good.
Should we add any ETW events as part of this? What about telemetry?
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JanProvaznik
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### Context PRs #12914 and #12868 showed that we need to be able to fix and normalize `AbsolutePath`. Corresponding methods for strings live in `FileUtilities.cs` that is a Shared file and cannot reference Framework classes like `AbsolutePath`. ### Changes Made - Moved some related functions to FrameworkFileUtilities class. - Added the needed functions for `AbsolutePath` ### Testing unit tests
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…#13079) ### Context PRs dotnet#12914 and dotnet#12868 showed that we need to be able to fix and normalize `AbsolutePath`. Corresponding methods for strings live in `FileUtilities.cs` that is a Shared file and cannot reference Framework classes like `AbsolutePath`. ### Changes Made - Moved some related functions to FrameworkFileUtilities class. - Added the needed functions for `AbsolutePath` ### Testing unit tests
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point brought up by @YuliiaKovalova should we decouple the classes of TaskHost and Sidecar? It seems a bit against the spirit of taskhosts and increases risk to existing scenarios to implement this pseudoworkernode functionality in the same class as the Taskhost which is supposed just to build a task and be done. |
JanProvaznik
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Pull request overview
Adds a design spec describing how to implement full IBuildEngine callback support when tasks execute in TaskHost, unblocking multithreaded (-mt) scenarios where tasks currently fail due to unsupported callbacks.
Changes:
- Introduces a new multithreading spec documenting current TaskHost callback gaps and failure modes.
- Proposes a bidirectional request/response packet protocol to forward callbacks to the parent node (including Yield/Reacquire).
- Describes threading and environment/working-directory state management, plus risks and a testing strategy.
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- Merge from main (brings in taskhost-threading.md from Stage 1) - Refactor to reference taskhost-threading.md instead of duplicating threading model, callback flow, cancellation semantics, lifecycle - Mark Q1 (connection loss) as resolved: OnLinkStatusChanged + MSB5027 - Update packet names: TaskHostIsRunningMultipleNodesRequest/Response - Add Stage 2+ design considerations section with per-stage analysis - Add cross-cutting state refactoring table for Stages 3/4 - Update terminology: parent -> owning worker node throughout - Update testing/file changes sections with actual Stage 1 deliverables - Add new key decisions (Shared location, env var pattern, specific packets) Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
- Mark RequestCores/ReleaseCores as implemented in status table - Rename TaskHostResourceRequest/Response to TaskHostCoresRequest/Response - Update phased rollout table with PR dotnet#13306 - Replace Stage 2 design considerations with implementation summary Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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#12863
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