/**
* 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.metrics2.impl;
import java.util.Random;
import java.util.concurrent.*;
import org.apache.hadoop.metrics2.lib.MetricMutableGaugeInt;
import org.apache.hadoop.metrics2.lib.MetricsRegistry;
import org.apache.hadoop.metrics2.lib.MetricMutableCounterInt;
import org.apache.hadoop.metrics2.lib.MetricMutableStat;
import org.apache.hadoop.metrics2.MetricsRecordBuilder;
import org.apache.hadoop.metrics2.util.Contracts;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.metrics2.Metric;
import org.apache.hadoop.metrics2.MetricsFilter;
import org.apache.hadoop.metrics2.MetricsSink;
/**
* An adapter class for metrics sink and associated filters
*/
class MetricsSinkAdapter {
private final Log LOG = LogFactory.getLog(MetricsSinkAdapter.class);
private final String name, description, context;
private final MetricsSink sink;
private final MetricsFilter sourceFilter, recordFilter, metricFilter;
private final SinkQueue<MetricsBuffer> queue;
private final Thread sinkThread;
private volatile boolean stopping = false;
private volatile boolean inError = false;
private final int period, firstRetryDelay, retryCount;
private final long oobPutTimeout;
private final float retryBackoff;
private final MetricsRegistry registry = new MetricsRegistry("sinkadapter");
private final MetricMutableStat latency;
private final MetricMutableCounterInt dropped;
private final MetricMutableGaugeInt qsize;
private final Consumer<MetricsBuffer> consumer =
new Consumer<MetricsBuffer>() {
public void consume(MetricsBuffer buffer) {
publishMetrics(buffer);
}
};
MetricsSinkAdapter(String name, String description, MetricsSink sink,
String context, MetricsFilter sourceFilter,
MetricsFilter recordFilter, MetricsFilter metricFilter,
int period, int queueCapacity, int retryDelay,
float retryBackoff, int retryCount) {
this.name = Contracts.checkNotNull(name, "name");
this.description = description;
this.sink = Contracts.checkNotNull(sink, "sink object");
this.context = context;
this.sourceFilter = sourceFilter;
this.recordFilter = recordFilter;
this.metricFilter = metricFilter;
this.period = Contracts.checkArg(period, period > 0, "period");
firstRetryDelay =
Contracts.checkArg(retryDelay, retryDelay > 0, "retry delay");
this.retryBackoff =
Contracts.checkArg(retryBackoff, retryBackoff > 1, "backoff factor");
oobPutTimeout = (long)
(firstRetryDelay * Math.pow(retryBackoff, retryCount) * 1000);
this.retryCount = retryCount;
this.queue = new SinkQueue<MetricsBuffer>(
Contracts.checkArg(queueCapacity, queueCapacity > 0, "queue capacity"));
latency = registry.newStat("sink."+ name +".latency",
"Sink end to end latency", "ops", "time");
dropped = registry.newCounter("sink."+ name +".dropped",
"Dropped updates per sink", 0);
qsize = registry.newGauge("sink."+ name + ".qsize", "Queue size", 0);
sinkThread = new Thread() {
@Override public void run() {
publishMetricsFromQueue();
}
};
sinkThread.setName(name);
sinkThread.setDaemon(true);
}
public boolean putMetricsImmediate(MetricsBuffer buffer) {
WaitableMetricsBuffer waitableBuffer =
new WaitableMetricsBuffer(buffer);
if (!queue.enqueue(waitableBuffer)) {
LOG.warn(name + " has a full queue and can't consume the given metrics.");
dropped.incr();
return false;
}
if (!waitableBuffer.waitTillNotified(oobPutTimeout)) {
LOG.warn(name +
" couldn't fulfill an immediate putMetrics request in time." +
" Abandoning.");
return false;
}
return true;
}
boolean putMetrics(MetricsBuffer buffer, long logicalTime) {
if (logicalTime % period == 0) {
LOG.debug("enqueue, logicalTime="+ logicalTime);
if (queue.enqueue(buffer)) return true;
dropped.incr();
return false;
}
return true; // OK
}
void publishMetricsFromQueue() {
int retryDelay = firstRetryDelay;
int n = retryCount;
int minDelay = Math.min(500, retryDelay * 1000); // millis
Random rng = new Random(System.nanoTime());
while (!stopping) {
try {
queue.consumeAll(consumer);
retryDelay = firstRetryDelay;
n = retryCount;
inError = false;
}
catch (InterruptedException e) {
LOG.info(name +" thread interrupted.");
}
catch (Exception e) {
if (n > 0) {
int awhile = rng.nextInt(retryDelay * 1000 - minDelay) + minDelay;
if (!inError) {
LOG.error("Got sink exception, retry in "+ awhile +"ms", e);
}
retryDelay *= retryBackoff;
try { Thread.sleep(awhile); }
catch (InterruptedException e2) {
LOG.info(name +" thread interrupted while waiting for retry", e2);
}
--n;
}
else {
if (!inError) {
LOG.error("Got sink exception and over retry limit, "+
"suppressing further error messages", e);
}
queue.clear();
inError = true; // Don't keep complaining ad infinitum
}
}
}
}
void publishMetrics(MetricsBuffer buffer) {
long ts = 0;
for (MetricsBuffer.Entry entry : buffer) {
LOG.debug("sourceFilter="+ sourceFilter);
if (sourceFilter == null || sourceFilter.accepts(entry.name())) {
for (MetricsRecordImpl record : entry.records()) {
if ((context == null || context.equals(record.context())) &&
(recordFilter == null || recordFilter.accepts(record))) {
if (LOG.isDebugEnabled()) {
LOG.debug("Pushing record "+ entry.name() +"."+ record.context() +
"."+ record.name() +" to "+ name);
}
sink.putMetrics(metricFilter == null
? record
: new MetricsRecordFiltered(record, metricFilter));
if (ts == 0) ts = record.timestamp();
}
}
}
}
if (ts > 0) {
sink.flush();
latency.add(System.currentTimeMillis() - ts);
}
if (buffer instanceof WaitableMetricsBuffer) {
((WaitableMetricsBuffer)buffer).notifyAnyWaiters();
}
LOG.debug("Done");
}
void start() {
sinkThread.start();
LOG.info("Sink "+ name +" started");
}
void stop() {
stopping = true;
sinkThread.interrupt();
try {
sinkThread.join();
}
catch (InterruptedException e) {
LOG.warn("Stop interrupted", e);
}
}
String name() {
return name;
}
String description() {
return description;
}
void snapshot(MetricsRecordBuilder rb, boolean all) {
registry.snapshot(rb, all);
}
MetricsSink sink() {
return sink;
}
static class WaitableMetricsBuffer extends MetricsBuffer {
private final Semaphore notificationSemaphore =
new Semaphore(0);
public WaitableMetricsBuffer(MetricsBuffer metricsBuffer) {
super(metricsBuffer);
}
public boolean waitTillNotified(long millisecondsToWait) {
try {
return notificationSemaphore.tryAcquire(millisecondsToWait,
TimeUnit.MILLISECONDS);
} catch (InterruptedException e) {
return false;
}
}
public void notifyAnyWaiters() {
notificationSemaphore.release();
}
}
}