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Packet Speaker Thread in a Coherence Node Can Become Blocked Trying to Lock a java.lang.DatagramPacket When Using either Java 7u80 or Java 8u40 and Later (Doc ID 2023934.1)

Last updated on MAY 13, 2022

Applies to:

Oracle Coherence - Version to [Release 12c]
Oracle Coherence - Version to [Release 12c]
Information in this document applies to any platform.


Issue encountered when running Coherence (where x=0,1,2,3,4) and (where y=0,1,2) and either Java 7u80 or Java 8u40 and higher, and the cluster is configured to use multicast and not well-known addresses (WKA) as the cluster discovery mechanism.

When the issue occurs a thread dump will show that either the publisher or speaker thread is waiting to lock an instance of, which is not locked by any other thread, for example:

As a consequence of this other nodes will report communication issues with the node, potentially leading to its ejection from the cluster.


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