Balazs Meszaros created HBASE-25307: ---------------------------------------
Summary: ThreadLocal pooling leads to NullPointerException Key: HBASE-25307 URL: https://issues.apache.org/jira/browse/HBASE-25307 Project: HBase Issue Type: Bug Components: Client Affects Versions: 3.0.0-alpha-1 Reporter: Balazs Meszaros Assignee: Balazs Meszaros We got NPE after setting {{hbase.client.ipc.pool.type}} to {{thread-local}}: {noformat} 20/11/18 01:53:04 ERROR yarn.ApplicationMaster: User class threw exception: java.lang.NullPointerException java.lang.NullPointerException at org.apache.hadoop.hbase.ipc.AbstractRpcClient.close(AbstractRpcClient.java:496) at org.apache.hadoop.hbase.client.ConnectionImplementation.close(ConnectionImplementation.java:1944) at org.apache.hadoop.hbase.mapreduce.TableInputFormatBase.close(TableInputFormatBase.java:660) {noformat} The root cause of the issue is probably at {{PoolMap.ThreadLocalPool.values()}}: {code:java} public Collection<R> values() { List<R> values = new ArrayList<>(); values.add(get()); return values; } {code} It adds {{null}} into the collection if the current thread does not have any resources which leads to NPE later. I traced the usages of values() and it should return every resource, not just that one which is attached to the caller thread. -- This message was sent by Atlassian Jira (v8.3.4#803005)