/*
* 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.cassandra.service;
import java.io.DataInputStream;
import java.io.DataOutput;
import java.io.IOException;
import java.lang.management.ManagementFactory;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Set;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;
import javax.management.MBeanServer;
import javax.management.ObjectName;
import com.google.common.util.concurrent.Futures;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.cassandra.cache.*;
import org.apache.cassandra.cache.AutoSavingCache.CacheSerializer;
import org.apache.cassandra.concurrent.Stage;
import org.apache.cassandra.concurrent.StageManager;
import org.apache.cassandra.config.DatabaseDescriptor;
import org.apache.cassandra.db.ColumnFamily;
import org.apache.cassandra.db.ColumnFamilyStore;
import org.apache.cassandra.db.DecoratedKey;
import org.apache.cassandra.db.RowIndexEntry;
import org.apache.cassandra.db.filter.QueryFilter;
import org.apache.cassandra.io.sstable.Descriptor;
import org.apache.cassandra.io.sstable.SSTableReader;
import org.apache.cassandra.io.sstable.SSTableReader.Operator;
import org.apache.cassandra.utils.ByteBufferUtil;
import org.apache.cassandra.utils.FBUtilities;
import org.apache.cassandra.utils.Pair;
public class CacheService implements CacheServiceMBean
{
private static final Logger logger = LoggerFactory.getLogger(CacheService.class);
public static final String MBEAN_NAME = "org.apache.cassandra.db:type=Caches";
public static enum CacheType
{
KEY_CACHE("KeyCache"),
ROW_CACHE("RowCache");
private final String name;
private CacheType(String typeName)
{
name = typeName;
}
public String toString()
{
return name;
}
}
public final static CacheService instance = new CacheService();
public final AutoSavingCache<KeyCacheKey, RowIndexEntry> keyCache;
public final AutoSavingCache<RowCacheKey, IRowCacheEntry> rowCache;
private CacheService()
{
MBeanServer mbs = ManagementFactory.getPlatformMBeanServer();
try
{
mbs.registerMBean(this, new ObjectName(MBEAN_NAME));
}
catch (Exception e)
{
throw new RuntimeException(e);
}
keyCache = initKeyCache();
rowCache = initRowCache();
}
/**
* @return auto saving cache object
*/
private AutoSavingCache<KeyCacheKey, RowIndexEntry> initKeyCache()
{
logger.info("Initializing key cache with capacity of {} MBs.", DatabaseDescriptor.getKeyCacheSizeInMB());
long keyCacheInMemoryCapacity = DatabaseDescriptor.getKeyCacheSizeInMB() * 1024 * 1024;
// as values are constant size we can use singleton weigher
// where 48 = 40 bytes (average size of the key) + 8 bytes (size of value)
ICache<KeyCacheKey, RowIndexEntry> kc;
kc = ConcurrentLinkedHashCache.create(keyCacheInMemoryCapacity);
AutoSavingCache<KeyCacheKey, RowIndexEntry> keyCache = new AutoSavingCache<KeyCacheKey, RowIndexEntry>(kc, CacheType.KEY_CACHE, new KeyCacheSerializer());
int keyCacheKeysToSave = DatabaseDescriptor.getKeyCacheKeysToSave();
logger.info("Scheduling key cache save to each {} seconds (going to save {} keys).",
DatabaseDescriptor.getKeyCacheSavePeriod(),
keyCacheKeysToSave == Integer.MAX_VALUE ? "all" : keyCacheKeysToSave);
keyCache.scheduleSaving(DatabaseDescriptor.getKeyCacheSavePeriod(), keyCacheKeysToSave);
return keyCache;
}
/**
* @return initialized row cache
*/
private AutoSavingCache<RowCacheKey, IRowCacheEntry> initRowCache()
{
logger.info("Initializing row cache with capacity of {} MBs", DatabaseDescriptor.getRowCacheSizeInMB());
long rowCacheInMemoryCapacity = DatabaseDescriptor.getRowCacheSizeInMB() * 1024 * 1024;
// cache object
ICache<RowCacheKey, IRowCacheEntry> rc = new SerializingCacheProvider().create(rowCacheInMemoryCapacity);
AutoSavingCache<RowCacheKey, IRowCacheEntry> rowCache = new AutoSavingCache<RowCacheKey, IRowCacheEntry>(rc, CacheType.ROW_CACHE, new RowCacheSerializer());
int rowCacheKeysToSave = DatabaseDescriptor.getRowCacheKeysToSave();
logger.info("Scheduling row cache save to each {} seconds (going to save {} keys).",
DatabaseDescriptor.getRowCacheSavePeriod(),
rowCacheKeysToSave == Integer.MAX_VALUE ? "all" : rowCacheKeysToSave);
rowCache.scheduleSaving(DatabaseDescriptor.getRowCacheSavePeriod(), rowCacheKeysToSave);
return rowCache;
}
public long getKeyCacheHits()
{
return keyCache.getMetrics().hits.count();
}
public long getRowCacheHits()
{
return rowCache.getMetrics().hits.count();
}
public long getKeyCacheRequests()
{
return keyCache.getMetrics().requests.count();
}
public long getRowCacheRequests()
{
return rowCache.getMetrics().requests.count();
}
public double getKeyCacheRecentHitRate()
{
return keyCache.getMetrics().getRecentHitRate();
}
public double getRowCacheRecentHitRate()
{
return rowCache.getMetrics().getRecentHitRate();
}
public int getRowCacheSavePeriodInSeconds()
{
return DatabaseDescriptor.getRowCacheSavePeriod();
}
public void setRowCacheSavePeriodInSeconds(int seconds)
{
if (seconds < 0)
throw new RuntimeException("RowCacheSavePeriodInSeconds must be non-negative.");
DatabaseDescriptor.setRowCacheSavePeriod(seconds);
rowCache.scheduleSaving(seconds, DatabaseDescriptor.getRowCacheKeysToSave());
}
public int getKeyCacheSavePeriodInSeconds()
{
return DatabaseDescriptor.getKeyCacheSavePeriod();
}
public void setKeyCacheSavePeriodInSeconds(int seconds)
{
if (seconds < 0)
throw new RuntimeException("KeyCacheSavePeriodInSeconds must be non-negative.");
DatabaseDescriptor.setKeyCacheSavePeriod(seconds);
keyCache.scheduleSaving(seconds, DatabaseDescriptor.getKeyCacheKeysToSave());
}
public int getRowCacheKeysToSave()
{
return DatabaseDescriptor.getRowCacheKeysToSave();
}
public void setRowCacheKeysToSave(int count)
{
if (count < 0)
throw new RuntimeException("RowCacheKeysToSave must be non-negative.");
DatabaseDescriptor.setRowCacheKeysToSave(count);
rowCache.scheduleSaving(getRowCacheSavePeriodInSeconds(), count);
}
public int getKeyCacheKeysToSave()
{
return DatabaseDescriptor.getKeyCacheKeysToSave();
}
public void setKeyCacheKeysToSave(int count)
{
if (count < 0)
throw new RuntimeException("KeyCacheKeysToSave must be non-negative.");
DatabaseDescriptor.setKeyCacheKeysToSave(count);
keyCache.scheduleSaving(getKeyCacheSavePeriodInSeconds(), count);
}
public void invalidateKeyCache()
{
keyCache.clear();
}
public void invalidateRowCache()
{
rowCache.clear();
}
public long getRowCacheCapacityInBytes()
{
return rowCache.getMetrics().capacity.value();
}
public long getRowCacheCapacityInMB()
{
return getRowCacheCapacityInBytes() / 1024 / 1024;
}
public void setRowCacheCapacityInMB(long capacity)
{
if (capacity < 0)
throw new RuntimeException("capacity should not be negative.");
rowCache.setCapacity(capacity * 1024 * 1024);
}
public long getKeyCacheCapacityInBytes()
{
return keyCache.getMetrics().capacity.value();
}
public long getKeyCacheCapacityInMB()
{
return getKeyCacheCapacityInBytes() / 1024 / 1024;
}
public void setKeyCacheCapacityInMB(long capacity)
{
if (capacity < 0)
throw new RuntimeException("capacity should not be negative.");
keyCache.setCapacity(capacity * 1024 * 1024);
}
public long getRowCacheSize()
{
return rowCache.getMetrics().size.value();
}
public long getRowCacheEntries()
{
return rowCache.size();
}
public long getKeyCacheSize()
{
return keyCache.getMetrics().size.value();
}
public long getKeyCacheEntries()
{
return keyCache.size();
}
public void saveCaches() throws ExecutionException, InterruptedException
{
List<Future<?>> futures = new ArrayList<Future<?>>(2);
logger.debug("submitting cache saves");
futures.add(keyCache.submitWrite(DatabaseDescriptor.getKeyCacheKeysToSave()));
futures.add(rowCache.submitWrite(DatabaseDescriptor.getRowCacheKeysToSave()));
FBUtilities.waitOnFutures(futures);
logger.debug("cache saves completed");
}
public class RowCacheSerializer implements CacheSerializer<RowCacheKey, IRowCacheEntry>
{
public void serialize(RowCacheKey key, DataOutput out) throws IOException
{
ByteBufferUtil.writeWithLength(key.key, out);
}
public Future<Pair<RowCacheKey, IRowCacheEntry>> deserialize(DataInputStream in, final ColumnFamilyStore cfs) throws IOException
{
final ByteBuffer buffer = ByteBufferUtil.readWithLength(in);
return StageManager.getStage(Stage.READ).submit(new Callable<Pair<RowCacheKey, IRowCacheEntry>>()
{
public Pair<RowCacheKey, IRowCacheEntry> call() throws Exception
{
DecoratedKey key = cfs.partitioner.decorateKey(buffer);
ColumnFamily data = cfs.getTopLevelColumns(QueryFilter.getIdentityFilter(key, cfs.name, Long.MIN_VALUE), Integer.MIN_VALUE);
return Pair.create(new RowCacheKey(cfs.metadata.cfId, key), (IRowCacheEntry) data);
}
});
}
}
public class KeyCacheSerializer implements CacheSerializer<KeyCacheKey, RowIndexEntry>
{
public void serialize(KeyCacheKey key, DataOutput out) throws IOException
{
RowIndexEntry entry = CacheService.instance.keyCache.get(key);
if (entry == null)
return;
ByteBufferUtil.writeWithLength(key.key, out);
Descriptor desc = key.desc;
out.writeInt(desc.generation);
out.writeBoolean(true);
RowIndexEntry.serializer.serialize(entry, out);
}
public Future<Pair<KeyCacheKey, RowIndexEntry>> deserialize(DataInputStream input, ColumnFamilyStore cfs) throws IOException
{
ByteBuffer key = ByteBufferUtil.readWithLength(input);
int generation = input.readInt();
SSTableReader reader = findDesc(generation, cfs.getSSTables());
input.readBoolean(); // backwards compatibility for "promoted indexes" boolean
if (reader == null)
{
RowIndexEntry.serializer.skipPromotedIndex(input);
return null;
}
RowIndexEntry entry = RowIndexEntry.serializer.deserialize(input, reader.descriptor.version);
return Futures.immediateFuture(Pair.create(new KeyCacheKey(reader.descriptor, key), entry));
}
private SSTableReader findDesc(int generation, Collection<SSTableReader> collection)
{
for (SSTableReader sstable : collection)
{
if (sstable.descriptor.generation == generation)
return sstable;
}
return null;
}
}
}