8269881: SA stack dump fails to include stack trace for SteadyStateThread

[plummercj]

The completely unrelated fix to JDK-8335124 led me to believe that the issue with sometimes not being able to get the stack trace of the SteadyStateThread might be due to the thread being active for a short period after being reported as in the Thread.State.BLOCKED state. Once set to that state, the thread still needs to call a native OS API to block the thread so it is truly idle. During this time the thread stack might be inconsistent and not walk-able. The fix is to add a short sleep after the thread has moved to the Thread.State.BLOCKED state to give it a chance to finish blocking.

Tested with Tier1 CI and all svc test tasks for tier2 and tier5.

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Progress

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Issue

• JDK-8269881: SA stack dump fails to include stack trace for SteadyStateThread (Bug - P4)

Reviewers

• Kevin Walls (@kevinjwalls - Reviewer)
• Serguei Spitsyn (@sspitsyn - Reviewer)

Reviewing

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