Implement proper thread-safety for concurrent ObjectMarker #137
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Introduce a ConcurrentBitField backed by an AtomicLongArray, and use it to do proper CAS-based state tracking in the concurrent ObjectMarker. This is a potential fix to issue #57.
jasonk000
commented
Aug 11, 2025
| import org.junit.Test; | ||
| import org.junit.rules.ExpectedException; | ||
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| public class ConcurrentBitFieldTest |
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Please suggest any additional / fixes to tests.
jasonk000
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Aug 11, 2025
| Bundle-SymbolicName: org.eclipse.mat.report;singleton:=true | ||
| Bundle-Version: 1.17.0.qualifier | ||
| Bundle-RequiredExecutionEnvironment: JavaSE-1.8 | ||
| Bundle-RequiredExecutionEnvironment: JavaSE-17 |
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This was required to support compareAndExchange. If we cannot do xchg, it can be done with compareAndSet, but involves additional CAS operations.
jasonk000
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Aug 11, 2025
| // Therefore, we need to use full compare and exchange rather than | ||
| // compare and set. | ||
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| while (true) |
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Appreciate any extra eyes on this!
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A colleague suggested adding a jcstress, did so in 9499a38.
Using a standalone project and readme since the jcstress modules are not made available for use with tycho or packaged in orbit. Added a README to explain.
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Introduce a ConcurrentBitField backed by an AtomicLongArray, and use it to do proper CAS-based state tracking in the concurrent ObjectMarker.
This is a potential fix to issue #57.