/**
* 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.lib;
import java.util.Collection;
import java.util.concurrent.ConcurrentMap;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.metrics.Interns;
import org.apache.hadoop.metrics2.MetricsException;
import org.apache.hadoop.metrics2.MetricsInfo;
import org.apache.hadoop.metrics2.MetricsRecordBuilder;
import org.apache.hadoop.metrics2.MetricsTag;
import org.apache.hadoop.metrics2.impl.MsInfo;
import com.google.common.base.Objects;
import com.google.common.collect.Maps;
/**
* An optional metrics registry class for creating and maintaining a
* collection of MetricsMutables, making writing metrics source easier.
* NOTE: this is a copy of org.apache.hadoop.metrics2.lib.MetricsRegistry with added one
* feature: metrics can be removed. When HADOOP-8313 is fixed, usages of this class
* should be substituted with org.apache.hadoop.metrics2.lib.MetricsRegistry.
* This implementation also provides handy methods for creating metrics
* dynamically.
* Another difference is that metricsMap implementation is substituted with
* thread-safe map, as we allow dynamic metrics additions/removals.
*/
@InterfaceAudience.Private
public class DynamicMetricsRegistry {
private static final Log LOG = LogFactory.getLog(DynamicMetricsRegistry.class);
private final ConcurrentMap<String, MutableMetric> metricsMap =
Maps.newConcurrentMap();
private final ConcurrentMap<String, MetricsTag> tagsMap =
Maps.newConcurrentMap();
private final MetricsInfo metricsInfo;
private final DefaultMetricsSystemHelper helper = new DefaultMetricsSystemHelper();
private final static String[] histogramSuffixes = new String[]{
"_num_ops",
"_min",
"_max",
"_median",
"_75th_percentile",
"_90th_percentile",
"_95th_percentile",
"_99th_percentile"};
/**
* Construct the registry with a record name
* @param name of the record of the metrics
*/
public DynamicMetricsRegistry(String name) {
this(Interns.info(name,name));
}
/**
* Construct the registry with a metadata object
* @param info the info object for the metrics record/group
*/
public DynamicMetricsRegistry(MetricsInfo info) {
metricsInfo = info;
}
/**
* @return the info object of the metrics registry
*/
public MetricsInfo info() {
return metricsInfo;
}
/**
* Get a metric by name
* @param name of the metric
* @return the metric object
*/
public MutableMetric get(String name) {
return metricsMap.get(name);
}
/**
* Get a tag by name
* @param name of the tag
* @return the tag object
*/
public MetricsTag getTag(String name) {
return tagsMap.get(name);
}
/**
* Create a mutable long integer counter
* @param name of the metric
* @param desc metric description
* @param iVal initial value
* @return a new counter object
*/
public MutableFastCounter newCounter(String name, String desc, long iVal) {
return newCounter(new MetricsInfoImpl(name, desc), iVal);
}
/**
* Create a mutable long integer counter
* @param info metadata of the metric
* @param iVal initial value
* @return a new counter object
*/
public MutableFastCounter newCounter(MetricsInfo info, long iVal) {
MutableFastCounter ret = new MutableFastCounter(info, iVal);
return addNewMetricIfAbsent(info.name(), ret, MutableFastCounter.class);
}
/**
* Create a mutable long integer gauge
* @param name of the metric
* @param desc metric description
* @param iVal initial value
* @return a new gauge object
*/
public MutableGaugeLong newGauge(String name, String desc, long iVal) {
return newGauge(new MetricsInfoImpl(name, desc), iVal);
}
/**
* Create a mutable long integer gauge
* @param info metadata of the metric
* @param iVal initial value
* @return a new gauge object
*/
public MutableGaugeLong newGauge(MetricsInfo info, long iVal) {
MutableGaugeLong ret = new MutableGaugeLong(info, iVal);
return addNewMetricIfAbsent(info.name(), ret, MutableGaugeLong.class);
}
/**
* Create a mutable metric with stats
* @param name of the metric
* @param desc metric description
* @param sampleName of the metric (e.g., "Ops")
* @param valueName of the metric (e.g., "Time" or "Latency")
* @param extended produce extended stat (stdev, min/max etc.) if true.
* @return a new mutable stat metric object
*/
public MutableStat newStat(String name, String desc,
String sampleName, String valueName, boolean extended) {
MutableStat ret =
new MutableStat(name, desc, sampleName, valueName, extended);
return addNewMetricIfAbsent(name, ret, MutableStat.class);
}
/**
* Create a mutable metric with stats
* @param name of the metric
* @param desc metric description
* @param sampleName of the metric (e.g., "Ops")
* @param valueName of the metric (e.g., "Time" or "Latency")
* @return a new mutable metric object
*/
public MutableStat newStat(String name, String desc,
String sampleName, String valueName) {
return newStat(name, desc, sampleName, valueName, false);
}
/**
* Create a mutable rate metric
* @param name of the metric
* @return a new mutable metric object
*/
public MutableRate newRate(String name) {
return newRate(name, name, false);
}
/**
* Create a mutable rate metric
* @param name of the metric
* @param description of the metric
* @return a new mutable rate metric object
*/
public MutableRate newRate(String name, String description) {
return newRate(name, description, false);
}
/**
* Create a mutable rate metric (for throughput measurement)
* @param name of the metric
* @param desc description
* @param extended produce extended stat (stdev/min/max etc.) if true
* @return a new mutable rate metric object
*/
public MutableRate newRate(String name, String desc, boolean extended) {
return newRate(name, desc, extended, true);
}
@InterfaceAudience.Private
public MutableRate newRate(String name, String desc,
boolean extended, boolean returnExisting) {
if (returnExisting) {
MutableMetric rate = metricsMap.get(name);
if (rate != null) {
if (rate instanceof MutableRate) return (MutableRate) rate;
throw new MetricsException("Unexpected metrics type "+ rate.getClass()
+" for "+ name);
}
}
MutableRate ret = new MutableRate(name, desc, extended);
return addNewMetricIfAbsent(name, ret, MutableRate.class);
}
/**
* Create a new histogram.
* @param name Name of the histogram.
* @return A new MutableHistogram
*/
public MutableHistogram newHistogram(String name) {
return newHistogram(name, "");
}
/**
* Create a new histogram.
* @param name The name of the histogram
* @param desc The description of the data in the histogram.
* @return A new MutableHistogram
*/
public MutableHistogram newHistogram(String name, String desc) {
MutableHistogram histo = new MutableHistogram(name, desc);
return addNewMetricIfAbsent(name, histo, MutableHistogram.class);
}
/**
* Create a new histogram with time range counts.
* @param name Name of the histogram.
* @return A new MutableTimeHistogram
*/
public MutableTimeHistogram newTimeHistogram(String name) {
return newTimeHistogram(name, "");
}
/**
* Create a new histogram with time range counts.
* @param name The name of the histogram
* @param desc The description of the data in the histogram.
* @return A new MutableTimeHistogram
*/
public MutableTimeHistogram newTimeHistogram(String name, String desc) {
MutableTimeHistogram histo = new MutableTimeHistogram(name, desc);
return addNewMetricIfAbsent(name, histo, MutableTimeHistogram.class);
}
/**
* Create a new histogram with size range counts.
* @param name Name of the histogram.
* @return A new MutableSizeHistogram
*/
public MutableSizeHistogram newSizeHistogram(String name) {
return newSizeHistogram(name, "");
}
/**
* Create a new histogram with size range counts.
* @param name The name of the histogram
* @param desc The description of the data in the histogram.
* @return A new MutableSizeHistogram
*/
public MutableSizeHistogram newSizeHistogram(String name, String desc) {
MutableSizeHistogram histo = new MutableSizeHistogram(name, desc);
return addNewMetricIfAbsent(name, histo, MutableSizeHistogram.class);
}
synchronized void add(String name, MutableMetric metric) {
addNewMetricIfAbsent(name, metric, MutableMetric.class);
}
/**
* Add sample to a stat metric by name.
* @param name of the metric
* @param value of the snapshot to add
*/
public void add(String name, long value) {
MutableMetric m = metricsMap.get(name);
if (m != null) {
if (m instanceof MutableStat) {
((MutableStat) m).add(value);
}
else {
throw new MetricsException("Unsupported add(value) for metric "+ name);
}
}
else {
metricsMap.put(name, newRate(name)); // default is a rate metric
add(name, value);
}
}
/**
* Set the metrics context tag
* @param name of the context
* @return the registry itself as a convenience
*/
public DynamicMetricsRegistry setContext(String name) {
return tag(MsInfo.Context, name, true);
}
/**
* Add a tag to the metrics
* @param name of the tag
* @param description of the tag
* @param value of the tag
* @return the registry (for keep adding tags)
*/
public DynamicMetricsRegistry tag(String name, String description, String value) {
return tag(name, description, value, false);
}
/**
* Add a tag to the metrics
* @param name of the tag
* @param description of the tag
* @param value of the tag
* @param override existing tag if true
* @return the registry (for keep adding tags)
*/
public DynamicMetricsRegistry tag(String name, String description, String value,
boolean override) {
return tag(new MetricsInfoImpl(name, description), value, override);
}
/**
* Add a tag to the metrics
* @param info metadata of the tag
* @param value of the tag
* @param override existing tag if true
* @return the registry (for keep adding tags etc.)
*/
public DynamicMetricsRegistry tag(MetricsInfo info, String value, boolean override) {
MetricsTag tag = Interns.tag(info, value);
if (!override) {
MetricsTag existing = tagsMap.putIfAbsent(info.name(), tag);
if (existing != null) {
throw new MetricsException("Tag "+ info.name() +" already exists!");
}
return this;
}
tagsMap.put(info.name(), tag);
return this;
}
public DynamicMetricsRegistry tag(MetricsInfo info, String value) {
return tag(info, value, false);
}
Collection<MetricsTag> tags() {
return tagsMap.values();
}
Collection<MutableMetric> metrics() {
return metricsMap.values();
}
/**
* Sample all the mutable metrics and put the snapshot in the builder
* @param builder to contain the metrics snapshot
* @param all get all the metrics even if the values are not changed.
*/
public void snapshot(MetricsRecordBuilder builder, boolean all) {
for (MetricsTag tag : tags()) {
builder.add(tag);
}
for (MutableMetric metric : metrics()) {
metric.snapshot(builder, all);
}
}
@Override public String toString() {
return Objects.toStringHelper(this)
.add("info", metricsInfo).add("tags", tags()).add("metrics", metrics())
.toString();
}
/**
* Removes metric by name
* @param name name of the metric to remove
*/
public void removeMetric(String name) {
helper.removeObjectName(name);
metricsMap.remove(name);
}
public void removeHistogramMetrics(String baseName) {
for (String suffix:histogramSuffixes) {
removeMetric(baseName+suffix);
}
}
/**
* Get a MetricMutableGaugeLong from the storage. If it is not there atomically put it.
*
* @param gaugeName name of the gauge to create or get.
* @param potentialStartingValue value of the new gauge if we have to create it.
*/
public MutableGaugeLong getGauge(String gaugeName, long potentialStartingValue) {
//Try and get the guage.
MutableMetric metric = metricsMap.get(gaugeName);
//If it's not there then try and put a new one in the storage.
if (metric == null) {
//Create the potential new gauge.
MutableGaugeLong newGauge = new MutableGaugeLong(new MetricsInfoImpl(gaugeName, ""),
potentialStartingValue);
// Try and put the gauge in. This is atomic.
metric = metricsMap.putIfAbsent(gaugeName, newGauge);
//If the value we get back is null then the put was successful and we will return that.
//otherwise gaugeLong should contain the thing that was in before the put could be completed.
if (metric == null) {
return newGauge;
}
}
if (!(metric instanceof MutableGaugeLong)) {
throw new MetricsException("Metric already exists in registry for metric name: " + gaugeName +
" and not of type MetricMutableGaugeLong");
}
return (MutableGaugeLong) metric;
}
/**
* Get a MetricMutableCounterLong from the storage. If it is not there atomically put it.
*
* @param counterName Name of the counter to get
* @param potentialStartingValue starting value if we have to create a new counter
*/
public MutableFastCounter getCounter(String counterName, long potentialStartingValue) {
//See getGauge for description on how this works.
MutableMetric counter = metricsMap.get(counterName);
if (counter == null) {
MutableFastCounter newCounter =
new MutableFastCounter(new MetricsInfoImpl(counterName, ""), potentialStartingValue);
counter = metricsMap.putIfAbsent(counterName, newCounter);
if (counter == null) {
return newCounter;
}
}
if (!(counter instanceof MutableCounter)) {
throw new MetricsException("Metric already exists in registry for metric name: " +
counterName + " and not of type MutableCounter");
}
return (MutableFastCounter) counter;
}
public MutableHistogram getHistogram(String histoName) {
//See getGauge for description on how this works.
MutableMetric histo = metricsMap.get(histoName);
if (histo == null) {
MutableHistogram newCounter =
new MutableHistogram(new MetricsInfoImpl(histoName, ""));
histo = metricsMap.putIfAbsent(histoName, newCounter);
if (histo == null) {
return newCounter;
}
}
if (!(histo instanceof MutableHistogram)) {
throw new MetricsException("Metric already exists in registry for metric name: " +
histoName + " and not of type MutableHistogram");
}
return (MutableHistogram) histo;
}
private<T extends MutableMetric> T
addNewMetricIfAbsent(String name,
T ret,
Class<T> metricClass) {
//If the value we get back is null then the put was successful and we will
// return that. Otherwise metric should contain the thing that was in
// before the put could be completed.
MutableMetric metric = metricsMap.putIfAbsent(name, ret);
if (metric == null) {
return ret;
}
return returnExistingWithCast(metric, metricClass, name);
}
@SuppressWarnings("unchecked")
private<T> T returnExistingWithCast(MutableMetric metric,
Class<T> metricClass, String name) {
if (!metricClass.isAssignableFrom(metric.getClass())) {
throw new MetricsException("Metric already exists in registry for metric name: " +
name + " and not of type " + metricClass +
" but instead of type " + metric.getClass());
}
return (T) metric;
}
public void clearMetrics() {
for (String name:metricsMap.keySet()) {
helper.removeObjectName(name);
}
metricsMap.clear();
}
}