ayushtkn commented on code in PR #6343: URL: https://github.com/apache/hive/pull/6343#discussion_r3005841369
########## ql/src/java/org/apache/hadoop/hive/ql/exec/tez/ExternalSessionsRegistry.java: ########## @@ -0,0 +1,79 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.apache.hadoop.hive.ql.exec.tez; + +import java.util.HashMap; +import java.util.Map; + +import org.apache.hadoop.conf.Configuration; +import org.apache.hadoop.hive.conf.HiveConf; +import org.apache.hadoop.hive.metastore.api.MetaException; +import org.apache.hadoop.hive.metastore.utils.JavaUtils; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +public interface ExternalSessionsRegistry { + Logger LOG = LoggerFactory.getLogger(ExternalSessionsRegistry.class); + + /** + * Returns application of id of the external session. + * @return application id + * @throws Exception in case of any exceptions + */ + String getSession() throws Exception; + + /** + * Returns external session back to registry. + * @param appId application id + */ + void returnSession(String appId); + + /** + * Closes the external session registry + */ + void close(); + + Map<String, ExternalSessionsRegistry> INSTANCES = new HashMap<>(); + + static ExternalSessionsRegistry getClient(final Configuration conf) { + ExternalSessionsRegistry registry; + synchronized (INSTANCES) { + // TODO: change this to TezConfiguration.TEZ_AM_REGISTRY_NAMESPACE after Tez 1.0.0 is released. + String namespace = conf.get("tez.am.registry.namespace"); + // HS2 would need to know about all coordinators running on all compute groups for a given compute (namespace) + // Setting this config to false in client, will make registry client listen on paths under @compute instead of + // @compute/compute-group + // TODO: change this to TezConfiguration.TEZ_AM_REGISTRY_ENABLE_COMPUTE_GROUPS after Tez 1.0.0 is released. + conf.setBoolean("tez.am.registry.enable.compute.groups", false); Review Comment: Should we do this conf.get or set inside the synchronized block? Even the logging? I believe we should keep the synchronized block as small as possible? and maybe we can avoid the double lookup using ``computeIfAbsent`` ``` conf.setBoolean("tez.am.registry.enable.compute.groups", false); String namespace = conf.get("tez.am.registry.namespace"); synchronized (INSTANCES) { // TODO: change this to TezConfiguration.TEZ_AM_REGISTRY_NAMESPACE after Tez 1.0.0 is released. // HS2 would need to know about all coordinators running on all compute groups for a given compute (namespace) // Setting this config to false in client, will make registry client listen on paths under @compute instead of // @compute/compute-group // TODO: change this to TezConfiguration.TEZ_AM_REGISTRY_ENABLE_COMPUTE_GROUPS after Tez 1.0.0 is released. registry = INSTANCES.computeIfAbsent(namespace, ns -> { try { String clazz = HiveConf.getVar(conf, HiveConf.ConfVars.HIVE_SERVER2_TEZ_EXTERNAL_SESSIONS_REGISTRY_CLASS); return JavaUtils.newInstance(JavaUtils.getClass(clazz, ExternalSessionsRegistry.class), new Class<?>[] {HiveConf.class}, new Object[] {conf}); } catch (MetaException e) { throw new RuntimeException(e); } }); } LOG.info("Returning tez external AM registry ({}) for namespace '{}'", System.identityHashCode(registry), namespace); return registry; ``` -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
