Exception in thread "node1_MemtablePostFlush:1" java.util.concurrent.RejectedExecutionException: MemtableReclaimMemory has shut down at org.apache.cassandra.concurrent.ThreadPoolExecutorBase.lambda$static$0(ThreadPoolExecutorBase.java:49) at org.apache.cassandra.concurrent.ThreadPoolExecutorJMXAdapter.lambda$rejectedExecutionHandler$0(ThreadPoolExecutorJMXAdapter.java:238) at java.base/java.util.concurrent.ThreadPoolExecutor.reject(ThreadPoolExecutor.java:825) at java.base/java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1355) at org.apache.cassandra.concurrent.ThreadPoolExecutorPlus.addTask(ThreadPoolExecutorPlus.java:50) at org.apache.cassandra.concurrent.ThreadPoolExecutorPlus.execute(ThreadPoolExecutorPlus.java:57) at org.apache.cassandra.utils.concurrent.ListenerList.safeExecute(ListenerList.java:166) at org.apache.cassandra.utils.concurrent.ListenerList.notifyListener(ListenerList.java:157) at org.apache.cassandra.utils.concurrent.ListenerList$RunnableWithExecutor.notifySelf(ListenerList.java:345) at org.apache.cassandra.utils.concurrent.ListenerList.lambda$notifyExclusive$0(ListenerList.java:124) at org.apache.cassandra.utils.concurrent.IntrusiveStack.forEach(IntrusiveStack.java:195) at org.apache.cassandra.utils.concurrent.ListenerList.notifyExclusive(ListenerList.java:124) at org.apache.cassandra.utils.concurrent.ListenerList.notify(ListenerList.java:96) at org.apache.cassandra.utils.concurrent.AsyncFuture.trySet(AsyncFuture.java:104) at org.apache.cassandra.utils.concurrent.AbstractFuture.trySuccess(AbstractFuture.java:143) at org.apache.cassandra.concurrent.FutureTask.run(FutureTask.java:71) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30) at java.base/java.lang.Thread.run(Thread.java:829)