java.lang.IllegalArgumentException: count outside allowed range: count=1142
at uk.co.real_logic.artio.messages.ControlNotificationEncoder$SessionsEncoder.wrap(ControlNotificationEncoder.java:226)
at uk.co.real_logic.artio.messages.ControlNotificationEncoder.sessionsCount(ControlNotificationEncoder.java:203)
at uk.co.real_logic.artio.protocol.GatewayPublication.saveControlNotification(GatewayPublication.java:1009)
at uk.co.real_logic.artio.engine.framer.Framer.saveControlNotification(Framer.java:1917)
at uk.co.real_logic.artio.engine.framer.Framer.onLibraryConnect(Framer.java:1851)
at uk.co.real_logic.artio.protocol.EngineProtocolSubscription.onLibraryConnect(EngineProtocolSubscription.java:224)
at uk.co.real_logic.artio.protocol.EngineProtocolSubscription.onFragment(EngineProtocolSubscription.java:80)
at uk.co.real_logic.artio.protocol.ProtocolSubscription.lambda$of$0(ProtocolSubscription.java:59)
at io.aeron.ControlledFragmentAssembler.onFragment(ControlledFragmentAssembler.java:123)
at io.aeron.Image.controlledPoll(Image.java:369)
at io.aeron.Subscription.controlledPoll(Subscription.java:235)
at uk.co.real_logic.artio.engine.framer.Framer.sendOutboundMessages(Framer.java:447)
at uk.co.real_logic.artio.engine.framer.Framer.doWork(Framer.java:382)
at org.agrona.concurrent.AgentRunner.doWork(AgentRunner.java:304)
at org.agrona.concurrent.AgentRunner.workLoop(AgentRunner.java:296)
at org.agrona.concurrent.AgentRunner.run(AgentRunner.java:162)
at java.base/java.lang.Thread.run(Thread.java:840)
This issue was due to the engine keeping offline sessions and attempting to encode more sessions than the encoding permits into a ControlNotification.