/*
* 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.geode.admin.internal;
import java.util.List;
import org.apache.logging.log4j.Logger;
import org.apache.geode.CancelException;
import org.apache.geode.admin.CacheHealthConfig;
import org.apache.geode.admin.GemFireHealthConfig;
import org.apache.geode.cache.CacheFactory;
import org.apache.geode.distributed.internal.DM;
import org.apache.geode.distributed.internal.InternalDistributedSystem;
import org.apache.geode.internal.OSProcess;
import org.apache.geode.internal.cache.CacheLifecycleListener;
import org.apache.geode.internal.cache.CachePerfStats;
import org.apache.geode.internal.cache.GemFireCacheImpl;
import org.apache.geode.internal.i18n.LocalizedStrings;
import org.apache.geode.internal.logging.LogService;
/**
* Contains the logic for evaluating the health of a GemFire <code>Cache</code> instance according
* to the thresholds provided in a {@link CacheHealthConfig}.
*
*
* @since GemFire 3.5
*/
class CacheHealthEvaluator extends AbstractHealthEvaluator implements CacheLifecycleListener {
private static final Logger logger = LogService.getLogger();
/** The config from which we get the evaulation criteria */
private CacheHealthConfig config;
/** The description of the cache being evaluated */
private String description;
/**
* Statistics about the <code>Cache</code> instance. If no cache has been created in this VM, this
* field will be <code>null</code>
*/
private CachePerfStats cacheStats;
/** The previous value of the netsearchTime stat (in nanoseconds) */
private long prevNetsearchTime;
/** The previous value of the netsearchedCompleted stat */
private long prevNetsearchesCompleted;
/** The previous value of the loadTime stat (in nanoseconds) */
private long prevLoadTime;
/** The previous value of the loadedCompleted stat */
private long prevLoadsCompleted;
/** The previous value of the gets stat */
private long prevGets;
////////////////////// Constructors //////////////////////
/**
* Creates a new <code>CacheHealthEvaluator</code>
*/
CacheHealthEvaluator(GemFireHealthConfig config, DM dm) {
super(config, dm);
this.config = config;
InternalDistributedSystem system = dm.getSystem();
GemFireCacheImpl cache;
try {
cache = (GemFireCacheImpl) CacheFactory.getInstance(system);
} catch (CancelException ex) {
// No cache in this VM
cache = null;
}
initialize(cache, dm);
GemFireCacheImpl.addCacheLifecycleListener(this);
}
//////////////////// Instance Methods ////////////////////
@Override
protected String getDescription() {
return this.description;
}
/**
* Initializes the state of this evaluator based on the given cache instance.
*/
private void initialize(GemFireCacheImpl cache, DM dm) {
StringBuffer sb = new StringBuffer();
if (cache != null) {
this.cacheStats = cache.getCachePerfStats();
sb.append("Cache \"");
sb.append(cache.getName());
sb.append("\"");
} else {
sb.append("No Cache");
}
sb.append(" in member ");
sb.append(dm.getId());
int pid = OSProcess.getId();
if (pid != 0) {
sb.append(" with pid ");
sb.append(pid);
}
this.description = sb.toString();
}
public void cacheCreated(GemFireCacheImpl cache) {
InternalDistributedSystem system = (InternalDistributedSystem) cache.getDistributedSystem();
DM dm = system.getDistributionManager();
initialize(cache, dm);
}
/**
* Checks to make sure that the average <code>netSearch</code> time during the previous health
* check interval is less than the {@linkplain CacheHealthConfig#getMaxNetSearchTime threshold}.
* If not, the status is "okay" health.
*
* @see CachePerfStats#getNetsearchTime
* @see CachePerfStats#getNetsearchesCompleted
*/
void checkNetSearchTime(List status) {
if (this.cacheStats == null || isFirstEvaluation() || this.cacheStats.isClosed()) {
return;
}
long deltaNetsearchTime = this.cacheStats.getNetsearchTime() - this.prevNetsearchTime;
long deltaNetsearchesCompleted =
this.cacheStats.getNetsearchesCompleted() - this.prevNetsearchesCompleted;
if (deltaNetsearchesCompleted != 0) {
long ratio = deltaNetsearchTime / deltaNetsearchesCompleted;
ratio /= 1000000;
long threshold = this.config.getMaxNetSearchTime();
if (ratio > threshold) {
String s =
LocalizedStrings.CacheHealthEvaluator_THE_AVERAGE_DURATION_OF_A_CACHE_NETSEARCH_0_MS_EXCEEDS_THE_THRESHOLD_1_MS
.toLocalizedString(new Object[] {ratio, threshold});
status.add(okayHealth(s));
}
}
}
/**
* Checks to make sure that the average <code>load</code> time during the previous health check
* interval is less than the {@linkplain CacheHealthConfig#getMaxLoadTime threshold}. If not, the
* status is "okay" health.
*
* @see CachePerfStats#getLoadTime
* @see CachePerfStats#getLoadsCompleted
*/
void checkLoadTime(List status) {
if (this.cacheStats == null || isFirstEvaluation() || this.cacheStats.isClosed()) {
return;
}
if (!isFirstEvaluation()) {
long deltaLoadTime = this.cacheStats.getLoadTime() - this.prevLoadTime;
long deltaLoadsCompleted = this.cacheStats.getLoadsCompleted() - this.prevLoadsCompleted;
if (logger.isDebugEnabled()) {
logger.debug("Completed {} loads in {} ms", deltaLoadsCompleted, (deltaLoadTime / 1000000));
}
if (deltaLoadsCompleted != 0) {
long ratio = deltaLoadTime / deltaLoadsCompleted;
ratio /= 1000000;
long threshold = this.config.getMaxLoadTime();
if (ratio > threshold) {
String s =
LocalizedStrings.CacheHealthEvaluator_THE_AVERAGE_DURATION_OF_A_CACHE_LOAD_0_MS_EXCEEDS_THE_THRESHOLD_1_MS
.toLocalizedString(new Object[] {ratio, threshold});
if (logger.isDebugEnabled()) {
logger.debug(s);
}
status.add(okayHealth(s));
}
}
}
}
/**
* Checks to make sure that the cache hit ratio during the previous health check interval is less
* than the {@linkplain CacheHealthConfig#getMinHitRatio threshold}. If not, the status is "okay"
* health.
*
* <P>
*
* The following formula is used to compute the hit ratio:
*
* <PRE>
* hitRatio = (gets - (loadsCompleted + netsearchesCompleted)) / (gets)
* </PRE>
*
*
* @see CachePerfStats#getGets
* @see CachePerfStats#getLoadsCompleted
* @see CachePerfStats#getNetsearchesCompleted
*/
void checkHitRatio(List status) {
if (this.cacheStats == null || isFirstEvaluation() || this.cacheStats.isClosed()) {
return;
}
long deltaGets = this.cacheStats.getGets() - this.prevGets;
if (deltaGets != 0) {
long deltaLoadsCompleted = this.cacheStats.getLoadsCompleted() - this.prevLoadsCompleted;
long deltaNetsearchesCompleted =
this.cacheStats.getNetsearchesCompleted() - this.prevNetsearchesCompleted;
double hits = (deltaGets - (deltaLoadsCompleted + deltaNetsearchesCompleted));
double hitRatio = hits / deltaGets;
double threshold = this.config.getMinHitRatio();
if (hitRatio < threshold) {
String s = "The hit ratio of this Cache (" + hitRatio + ") is below the threshold ("
+ threshold + ")";
status.add(okayHealth(s));
}
}
}
/**
* Checks to make sure that the {@linkplain CachePerfStats#getEventQueueSize cache event queue
* size} does not exceed the {@linkplain CacheHealthConfig#getMaxEventQueueSize threshold}. If it
* does, the status is "okay" health.
*/
void checkEventQueueSize(List status) {
if (this.cacheStats == null || isFirstEvaluation() || this.cacheStats.isClosed()) {
return;
}
long eventQueueSize = this.cacheStats.getEventQueueSize();
long threshold = this.config.getMaxEventQueueSize();
if (eventQueueSize > threshold) {
String s =
LocalizedStrings.CacheHealthEvaluator_THE_SIZE_OF_THE_CACHE_EVENT_QUEUE_0_MS_EXCEEDS_THE_THRESHOLD_1_MS
.toLocalizedString(
new Object[] {Long.valueOf(eventQueueSize), Long.valueOf(threshold)});
status.add(okayHealth(s));
}
}
/**
* Updates the previous values of statistics
*/
private void updatePrevious() {
if (this.cacheStats != null && !this.cacheStats.isClosed()) {
this.prevLoadTime = this.cacheStats.getLoadTime();
this.prevLoadsCompleted = this.cacheStats.getLoadsCompleted();
this.prevNetsearchTime = this.cacheStats.getNetsearchTime();
this.prevNetsearchesCompleted = this.cacheStats.getNetsearchesCompleted();
this.prevGets = this.cacheStats.getGets();
} else {
this.prevLoadTime = 0L;
this.prevLoadsCompleted = 0L;
this.prevNetsearchTime = 0L;
this.prevNetsearchesCompleted = 0L;
this.prevGets = 0L;
}
}
@Override
protected void check(List status) {
checkNetSearchTime(status);
checkLoadTime(status);
checkHitRatio(status);
checkEventQueueSize(status);
updatePrevious();
}
@Override
public void close() {
GemFireCacheImpl.removeCacheLifecycleListener(this);
}
@Override
public void cacheClosed(GemFireCacheImpl cache) {
// do nothing
}
}