BukrosSzabolcs commented on a change in pull request #592: HBASE-22982: region server suspend/resume and graceful rolling restart actions URL: https://github.com/apache/hbase/pull/592#discussion_r328133706
########## File path: hbase-it/src/test/java/org/apache/hadoop/hbase/chaos/actions/RollingBatchSuspendResumeRsAction.java ########## @@ -0,0 +1,116 @@ +/** + * 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.hbase.chaos.actions; + +import java.io.IOException; +import java.util.LinkedList; +import java.util.List; +import java.util.Queue; + +import org.apache.commons.lang3.RandomUtils; +import org.apache.hadoop.hbase.ServerName; +import org.apache.hadoop.hbase.chaos.monkies.PolicyBasedChaosMonkey; +import org.apache.hadoop.hbase.util.Threads; +import org.apache.hadoop.util.Shell; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +/** + * Suspend then resume a ratio of the regionservers in a rolling fashion. At each step, either + * suspend a server, or resume one, sleeping (sleepTime) in between steps. The parameter + * maxSuspendedServers limits the maximum number of servers that can be down at the same time + * during rolling restarts. + */ +public class RollingBatchSuspendResumeRsAction extends Action { + private static final Logger LOG = + LoggerFactory.getLogger(RollingBatchSuspendResumeRsAction.class); + private float ratio; + private long sleepTime; + private int maxSuspendedServers; // number of maximum suspended servers at any given time. + + public RollingBatchSuspendResumeRsAction(long sleepTime, float ratio) { + this(sleepTime, ratio, 5); + } + + public RollingBatchSuspendResumeRsAction(long sleepTime, float ratio, int maxSuspendedServers) { + this.ratio = ratio; + this.sleepTime = sleepTime; + this.maxSuspendedServers = maxSuspendedServers; + } + + enum SuspendOrResume { + SUSPEND, RESUME + } + + @Override public void perform() throws Exception { + LOG.info(String.format("Performing action: Rolling batch restarting %d%% of region servers", + (int) (ratio * 100))); + List<ServerName> selectedServers = selectServers(); + + Queue<ServerName> serversToBeSuspended = new LinkedList<>(selectedServers); + Queue<ServerName> suspendedServers = new LinkedList<>(); + + // loop while there are servers to be suspended or suspended servers to be resumed + while ((!serversToBeSuspended.isEmpty() || !suspendedServers.isEmpty()) && !context + .isStopping()) { + SuspendOrResume action; + + if (serversToBeSuspended.isEmpty()) { // no more servers to suspend + action = SuspendOrResume.RESUME; + } else if (suspendedServers.isEmpty()) { + action = SuspendOrResume.SUSPEND; // no more servers to resume + } else if (suspendedServers.size() >= maxSuspendedServers) { + // we have too many suspended servers. Don't suspend any more + action = SuspendOrResume.RESUME; + } else { + // do a coin toss + action = RandomUtils.nextBoolean() ? SuspendOrResume.SUSPEND : SuspendOrResume.RESUME; + } + + ServerName server; + switch (action) { + case SUSPEND: + server = serversToBeSuspended.remove(); + try { + suspendRs(server); + } catch (Shell.ExitCodeException e) { + LOG.info("Problem suspending but presume successful; code=" + e.getExitCode(), e); Review comment: Done ---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services
