[release/7.0] Disable EventSource support in NativeAOT by default #76052
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`DiagnosticSource` is currently not AOT compatible. If a machine-wide DiagnosticSource-related event listener is enabled (such as PerfView, or possibly even a managed VS debugging session) it activates `DiagnosticSource` code paths within the executable and basically injects a runtime failure into NativeAOT processes due to the AOT-incompatibility of the code. E.g. trying to do a `HttpClient` web request with PerfView collecting in the background causes a runtime exception to be thrown. This uses the documented switch to disable `EventSource` support (unless the user specified a different value). Indirectly, it disables `DiagnosticSource` as well. As a side effect, disabling `EventSource` drops the size of a NativeAOT-compiled Hello World from 3.48 MB to 2.85 MB 🥳.
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I couldn't figure out the best area label to add to this PR. If you have write-permissions please help me learn by adding exactly one area label. |
MichalStrehovsky
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Servicing-consider
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/azp run runtime-extra-platforms |
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Azure Pipelines successfully started running 1 pipeline(s). |
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This needs test fixes from #76114 |
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/azp run runtime-extra-platforms |
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Azure Pipelines successfully started running 1 pipeline(s). |
I cherry picked the necessary fixes in d97afaf. I assume those are de minimis test fixes that don't need extra reviewing. (I don't understand how I missed those failures. I even wrote a regex to help me filter the known failing and unrelated tests in extra-platforms :/. There were many unrelated failures.) |
When there are many unrelated failures, people always miss new ones even when super careful. It happened to me multiple times. If we end up in a state with many unrelated failures, we need to make fixing that a top priority. |
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/azp run runtime-extra-platforms |
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Azure Pipelines successfully started running 1 pipeline(s). |
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@MichalStrehovsky don't forget to send the email to Tactics requesting approval, if you haven't done so. |
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@MichalStrehovsky please check the failed tests as well. |
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The failures in Mono legs are unrelated. |
carlossanlop
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This was approved by Tactics via email along with #76056 CI failures are:
Signed off. Ready to merge |
ghost
locked as resolved and limited conversation to collaborators
Backport of #76000 to release/7.0
/cc @MichalStrehovsky
Customer Impact
DiagnosticSourceis currently not AOT compatible. If a machine-wide DiagnosticSource-related event listener is enabled (such as PerfView, or possibly even a managed VS debugging session) it activatesDiagnosticSourcecode paths within the executable and basically injects a runtime failure into NativeAOT processes due to the AOT-incompatibility of the code.E.g. trying to do a
HttpClientweb request with PerfView collecting in the background causes a runtime exception to be thrown.This uses the documented switch to disable
EventSourcesupport (unless the user specified a different value). Indirectly, it disablesDiagnosticSourceas well.Testing
All NativeAOT testing.
Risk
This is a supported switch that we're just changing the default value for. The risk is low.