/**
* 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 org.apache.hadoop.hbase.io.hfile.bucket;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.LongAdder;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.io.hfile.CacheStats;
import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
/**
* Class that implements cache metrics for bucket cache.
*/
@InterfaceAudience.Private
public class BucketCacheStats extends CacheStats {
private final LongAdder ioHitCount = new LongAdder();
private final LongAdder ioHitTime = new LongAdder();
private static final long NANO_TIME = TimeUnit.MILLISECONDS.toNanos(1);
private long lastLogTime = EnvironmentEdgeManager.currentTime();
BucketCacheStats() {
super("BucketCache");
}
@Override
public String toString() {
return super.toString() + ", ioHitsPerSecond=" + getIOHitsPerSecond() +
", ioTimePerHit=" + getIOTimePerHit();
}
public void ioHit(long time) {
ioHitCount.increment();
ioHitTime.add(time);
}
public long getIOHitsPerSecond() {
long now = EnvironmentEdgeManager.currentTime();
long took = (now - lastLogTime) / 1000;
lastLogTime = now;
return took == 0 ? 0 : ioHitCount.sum() / took;
}
public double getIOTimePerHit() {
long time = ioHitTime.sum() / NANO_TIME;
long count = ioHitCount.sum();
return ((float) time / (float) count);
}
public void reset() {
ioHitCount.reset();
ioHitTime.reset();
}
}