/**
* Copyright The Apache Software Foundation
*
* 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 com.alibaba.wasp.fserver;
import com.alibaba.wasp.ServerName;
import com.alibaba.wasp.fserver.metrics.MetricsFServerWrapper;
import com.alibaba.wasp.metrics.MetricsExecutor;
import com.alibaba.wasp.zookeeper.ZooKeeperWatcher;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;
/**
* Impl for exposing FServer Information through Hadoop's metrics 2 system.
*/
public class MetricsFServerWrapperImpl implements MetricsFServerWrapper {
public static final Log LOG = LogFactory.getLog(MetricsFServerWrapperImpl.class);
public static final int PERIOD = 15;
private final FServer fserver;
private ScheduledExecutorService executor;
private Runnable runnable;
private volatile double requestsPerSecond = 0.0;
private volatile double readRequestsPerSecond = 0.0;
private volatile double writeRequestsPerSecond = 0.0;
public MetricsFServerWrapperImpl(final FServer fserver) {
this.fserver = fserver;
this.executor = MetricsExecutor.getExecutor();
this.runnable = new FServerMetricsWrapperRunnable();
this.executor.scheduleWithFixedDelay(this.runnable, PERIOD, PERIOD,
TimeUnit.SECONDS);
}
@Override
public String getServerName() {
ServerName serverName = fserver.getServerName();
if (serverName == null) {
return "";
}
return serverName.getServerName();
}
@Override
public String getClusterId() {
return fserver.getClusterId();
}
@Override
public String getZookeeperQuorum() {
ZooKeeperWatcher zk = fserver.getZooKeeper();
if (zk == null) {
return "";
}
return zk.getQuorum();
}
@Override
public long getStartCode() {
return fserver.getStartcode();
}
@Override
public long getNumOnlineEntityGroups() {
return fserver.getNumberOfOnlineEntityGroups();
}
@Override
public double getRequestsPerSecond() {
return this.requestsPerSecond;
}
@Override
public double getReadRequestsPerSecond() {
return this.readRequestsPerSecond;
}
@Override
public double getWriteRequestsPerSecond() {
return this.writeRequestsPerSecond;
}
@Override
public void forceRecompute() {
this.runnable.run();
}
/**
* This is the runnable that will be executed on the executor every PERIOD
* number of seconds It will take metrics/numbers from all of the entity
* pgropus and use them to compute point in time metrics.
*/
public class FServerMetricsWrapperRunnable implements Runnable {
private long lastRan = 0;
private long lastReadRequestCount = 0;
private long lastWriteRequestCount = 0;
@Override
synchronized public void run() {
long tempReadRequestsCount = 0;
long tempWriteRequestsCount = 0;
for (EntityGroup eg : fserver.getOnlineEntityGroupsLocalContext()) {
tempReadRequestsCount += eg.readRequestsCount.get();
tempWriteRequestsCount += eg.writeRequestsCount.get();
}
// Compute the number of requests per second
long currentTime = EnvironmentEdgeManager.currentTimeMillis();
// assume that it took PERIOD seconds to start the executor.
// this is a guess but it's a pretty good one.
if (lastRan == 0) {
lastRan = currentTime - (PERIOD * 1000);
}
// If we've time traveled keep the last requests per second.
if ((currentTime - lastRan) > 10) {
readRequestsPerSecond = (tempReadRequestsCount - lastReadRequestCount)
/ ((currentTime - lastRan) / 1000.0);
writeRequestsPerSecond = (tempWriteRequestsCount - lastWriteRequestCount)
/ ((currentTime - lastRan) / 1000.0);
requestsPerSecond = readRequestsPerSecond + writeRequestsPerSecond;
lastReadRequestCount = tempReadRequestsCount;
lastWriteRequestCount = tempWriteRequestsCount;
}
lastRan = currentTime;
// Copy over computed values so that no thread sees half computed values.
}
}
}