[He Plugin]RejectedExecutionException occurred after connecting 80 switches(mininet)

When I connected 80 switches to controller using redist/beryllium-sr3 version, we had issue which manifested through this exception:
Exception in thread "Thread-351" java.util.concurrent.RejectedExecutionException: Task org.opendaylight.openflowplugin.openflow.md.core.HandshakeStepWrapper@3803f462 rejected from org.opendaylight.openflowplugin.openflow.md.core.ThreadPoolLoggingExecutor@3c3c77ba[Shutting down, pool size = 0, active threads = 0, queued tasks = 1, completed tasks = 0]
at java.util.concurrent.ThreadPoolExecutor$AbortPolicy.rejectedExecution(ThreadPoolExecutor.java:2047)
at java.util.concurrent.ThreadPoolExecutor.reject(ThreadPoolExecutor.java:823)
at java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1369)
at org.opendaylight.openflowplugin.openflow.md.core.ConnectionConductorImpl.onConnectionReady(ConnectionConductorImpl.java:451)
at org.opendaylight.openflowjava.protocol.impl.core.connection.ConnectionAdapterImpl$1.run(ConnectionAdapterImpl.java:185)
at java.lang.Thread.run(Thread.java:745)