GH-2787: Deadlock in JenaSystem.init() - Githubissues

apache / jena

Apache Jena

https://jena.apache.org/

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GH-2787: Deadlock in JenaSystem.init() #2792

Closed arne-bdt closed 1 month ago

arne-bdt commented 1 month ago

Added a fail-fast mechanism: now throwing an ExceptionInInitializerError when a thread attempts to enter JenaSystem.init() while another thread is in the initialization process.

Refactored JenaSystem.init() using the "Initialization-on-demand holder idiom" for simpler and safer initialization.

Additionally, I have added integration tests for JenaSystem.init(), including the parallel execution scenario from the issue, to ensure coverage of potential concurrency issues.

GitHub issue resolved #2787

[x] Tests are included.
[x] Commits have been squashed to remove intermediate development commit messages.
[x] Key commit messages start with the issue number (GH-xxxx)

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afs commented 1 month ago

I'm unsure about this PR,

I set this PR to "draft" - hope you don't mind.

arne-bdt commented 1 month ago

I found another "solution": Added a fail-fast mechanism: now throwing an ExceptionInInitializerError when a thread attempts to enter JenaSystem.init() while another thread is in the initialization process.

What do you think?

afs commented 1 month ago

I think requiring single threaded initialization will break existing usage. Until we agree that it is the only option, I don't think we should go that way.

Discussion on the issue.

arne-bdt commented 1 month ago

see https://github.com/apache/jena/issues/2787#issuecomment-2435110319