JMS connectivity time is jumping from 70ms up to 1.5 seconds.

Issue

• Why the JMS connectivity time is jumping from 70ms up to 1.5 seconds.
• Some of the threads which were consuming high CPU were noticed as following:

"ActiveMQ Broker[amq] Scheduler" daemon prio=10 tid=0x00007f0eac233800 nid=0x2165 runnable [0x00007f0f16b3c000]
   java.lang.Thread.State: RUNNABLE
    at org.apache.activemq.broker.region.cursors.StoreQueueCursor.getNextCursor(StoreQueueCursor.java:288)
    - locked <0x00000005f5653060> (a org.apache.activemq.broker.region.cursors.StoreQueueCursor)
    at org.apache.activemq.broker.region.cursors.StoreQueueCursor.hasNext(StoreQueueCursor.java:126)
    - locked <0x00000005f5653060> (a org.apache.activemq.broker.region.cursors.StoreQueueCursor)
    at org.apache.activemq.broker.region.Queue.doPageInForDispatch(Queue.java:1962)
    at org.apache.activemq.broker.region.Queue.pageInMessages(Queue.java:2182)
    at org.apache.activemq.broker.region.Queue.doBrowse(Queue.java:1183)
    at org.apache.activemq.broker.region.Queue.expireMessages(Queue.java:977)
    at org.apache.activemq.broker.region.Queue.access$100(Queue.java:103)
    at org.apache.activemq.broker.region.Queue$2.run(Queue.java:147)
    at org.apache.activemq.thread.SchedulerTimerTask.run(SchedulerTimerTask.java:33)
    at java.util.TimerThread.mainLoop(Timer.java:555)
    at java.util.TimerThread.run(Timer.java:505)