| /** |
| * 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.io.File; |
| import java.io.FileInputStream; |
| import java.io.FileOutputStream; |
| import java.io.IOException; |
| import java.nio.ByteBuffer; |
| import java.util.ArrayList; |
| import java.util.Comparator; |
| import java.util.HashSet; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.NavigableSet; |
| import java.util.PriorityQueue; |
| import java.util.Set; |
| import java.util.concurrent.ArrayBlockingQueue; |
| import java.util.concurrent.BlockingQueue; |
| import java.util.concurrent.ConcurrentHashMap; |
| import java.util.concurrent.ConcurrentMap; |
| import java.util.concurrent.ConcurrentSkipListSet; |
| import java.util.concurrent.Executors; |
| import java.util.concurrent.ScheduledExecutorService; |
| import java.util.concurrent.TimeUnit; |
| import java.util.concurrent.atomic.AtomicBoolean; |
| import java.util.concurrent.atomic.AtomicLong; |
| import java.util.concurrent.atomic.LongAdder; |
| import java.util.concurrent.locks.Lock; |
| import java.util.concurrent.locks.ReentrantLock; |
| import java.util.concurrent.locks.ReentrantReadWriteLock; |
| import java.util.function.Consumer; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.hbase.HBaseConfiguration; |
| import org.apache.hadoop.hbase.TableName; |
| import org.apache.hadoop.hbase.client.Admin; |
| import org.apache.hadoop.hbase.io.ByteBuffAllocator; |
| import org.apache.hadoop.hbase.io.ByteBuffAllocator.Recycler; |
| import org.apache.hadoop.hbase.io.HeapSize; |
| import org.apache.hadoop.hbase.io.hfile.BlockCache; |
| import org.apache.hadoop.hbase.io.hfile.BlockCacheKey; |
| import org.apache.hadoop.hbase.io.hfile.BlockCacheUtil; |
| import org.apache.hadoop.hbase.io.hfile.BlockPriority; |
| import org.apache.hadoop.hbase.io.hfile.BlockType; |
| import org.apache.hadoop.hbase.io.hfile.CacheStats; |
| import org.apache.hadoop.hbase.io.hfile.Cacheable; |
| import org.apache.hadoop.hbase.io.hfile.CachedBlock; |
| import org.apache.hadoop.hbase.io.hfile.HFileBlock; |
| import org.apache.hadoop.hbase.nio.ByteBuff; |
| import org.apache.hadoop.hbase.nio.RefCnt; |
| import org.apache.hadoop.hbase.protobuf.ProtobufMagic; |
| import org.apache.hadoop.hbase.util.EnvironmentEdgeManager; |
| import org.apache.hadoop.hbase.util.IdReadWriteLock; |
| import org.apache.hadoop.hbase.util.IdReadWriteLockStrongRef; |
| import org.apache.hadoop.hbase.util.IdReadWriteLockWithObjectPool; |
| import org.apache.hadoop.hbase.util.IdReadWriteLockWithObjectPool.ReferenceType; |
| import org.apache.hadoop.util.StringUtils; |
| import org.apache.yetus.audience.InterfaceAudience; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import org.apache.hbase.thirdparty.com.google.common.base.Preconditions; |
| import org.apache.hbase.thirdparty.com.google.common.util.concurrent.ThreadFactoryBuilder; |
| |
| import org.apache.hadoop.hbase.shaded.protobuf.generated.BucketCacheProtos; |
| |
| /** |
| * BucketCache uses {@link BucketAllocator} to allocate/free blocks, and uses |
| * BucketCache#ramCache and BucketCache#backingMap in order to |
| * determine if a given element is in the cache. The bucket cache can use on-heap or |
| * off-heap memory {@link ByteBufferIOEngine} or in a file {@link FileIOEngine} to |
| * store/read the block data. |
| * |
| * <p>Eviction is via a similar algorithm as used in |
| * {@link org.apache.hadoop.hbase.io.hfile.LruBlockCache} |
| * |
| * <p>BucketCache can be used as mainly a block cache (see |
| * {@link org.apache.hadoop.hbase.io.hfile.CombinedBlockCache}), combined with |
| * a BlockCache to decrease CMS GC and heap fragmentation. |
| * |
| * <p>It also can be used as a secondary cache (e.g. using a file on ssd/fusionio to store |
| * blocks) to enlarge cache space via a victim cache. |
| */ |
| @InterfaceAudience.Private |
| public class BucketCache implements BlockCache, HeapSize { |
| private static final Logger LOG = LoggerFactory.getLogger(BucketCache.class); |
| |
| /** Priority buckets config */ |
| static final String SINGLE_FACTOR_CONFIG_NAME = "hbase.bucketcache.single.factor"; |
| static final String MULTI_FACTOR_CONFIG_NAME = "hbase.bucketcache.multi.factor"; |
| static final String MEMORY_FACTOR_CONFIG_NAME = "hbase.bucketcache.memory.factor"; |
| static final String EXTRA_FREE_FACTOR_CONFIG_NAME = "hbase.bucketcache.extrafreefactor"; |
| static final String ACCEPT_FACTOR_CONFIG_NAME = "hbase.bucketcache.acceptfactor"; |
| static final String MIN_FACTOR_CONFIG_NAME = "hbase.bucketcache.minfactor"; |
| |
| /** Use strong reference for offsetLock or not */ |
| private static final String STRONG_REF_KEY = "hbase.bucketcache.offsetlock.usestrongref"; |
| private static final boolean STRONG_REF_DEFAULT = false; |
| |
| /** Priority buckets */ |
| static final float DEFAULT_SINGLE_FACTOR = 0.25f; |
| static final float DEFAULT_MULTI_FACTOR = 0.50f; |
| static final float DEFAULT_MEMORY_FACTOR = 0.25f; |
| static final float DEFAULT_MIN_FACTOR = 0.85f; |
| |
| private static final float DEFAULT_EXTRA_FREE_FACTOR = 0.10f; |
| private static final float DEFAULT_ACCEPT_FACTOR = 0.95f; |
| |
| // Number of blocks to clear for each of the bucket size that is full |
| private static final int DEFAULT_FREE_ENTIRE_BLOCK_FACTOR = 2; |
| |
| /** Statistics thread */ |
| private static final int statThreadPeriod = 5 * 60; |
| |
| final static int DEFAULT_WRITER_THREADS = 3; |
| final static int DEFAULT_WRITER_QUEUE_ITEMS = 64; |
| |
| // Store/read block data |
| transient final IOEngine ioEngine; |
| |
| // Store the block in this map before writing it to cache |
| transient final RAMCache ramCache; |
| // In this map, store the block's meta data like offset, length |
| transient ConcurrentHashMap<BlockCacheKey, BucketEntry> backingMap; |
| |
| /** |
| * Flag if the cache is enabled or not... We shut it off if there are IO |
| * errors for some time, so that Bucket IO exceptions/errors don't bring down |
| * the HBase server. |
| */ |
| private volatile boolean cacheEnabled; |
| |
| /** |
| * A list of writer queues. We have a queue per {@link WriterThread} we have running. |
| * In other words, the work adding blocks to the BucketCache is divided up amongst the |
| * running WriterThreads. Its done by taking hash of the cache key modulo queue count. |
| * WriterThread when it runs takes whatever has been recently added and 'drains' the entries |
| * to the BucketCache. It then updates the ramCache and backingMap accordingly. |
| */ |
| transient final ArrayList<BlockingQueue<RAMQueueEntry>> writerQueues = new ArrayList<>(); |
| transient final WriterThread[] writerThreads; |
| |
| /** Volatile boolean to track if free space is in process or not */ |
| private volatile boolean freeInProgress = false; |
| private transient final Lock freeSpaceLock = new ReentrantLock(); |
| |
| private final LongAdder realCacheSize = new LongAdder(); |
| private final LongAdder heapSize = new LongAdder(); |
| /** Current number of cached elements */ |
| private final LongAdder blockNumber = new LongAdder(); |
| |
| /** Cache access count (sequential ID) */ |
| private final AtomicLong accessCount = new AtomicLong(); |
| |
| private static final int DEFAULT_CACHE_WAIT_TIME = 50; |
| |
| /** |
| * Used in tests. If this flag is false and the cache speed is very fast, |
| * bucket cache will skip some blocks when caching. If the flag is true, we |
| * will wait until blocks are flushed to IOEngine. |
| */ |
| boolean wait_when_cache = false; |
| |
| private final BucketCacheStats cacheStats = new BucketCacheStats(); |
| |
| private final String persistencePath; |
| private final long cacheCapacity; |
| /** Approximate block size */ |
| private final long blockSize; |
| |
| /** Duration of IO errors tolerated before we disable cache, 1 min as default */ |
| private final int ioErrorsTolerationDuration; |
| // 1 min |
| public static final int DEFAULT_ERROR_TOLERATION_DURATION = 60 * 1000; |
| |
| // Start time of first IO error when reading or writing IO Engine, it will be |
| // reset after a successful read/write. |
| private volatile long ioErrorStartTime = -1; |
| |
| /** |
| * A ReentrantReadWriteLock to lock on a particular block identified by offset. |
| * The purpose of this is to avoid freeing the block which is being read. |
| * <p> |
| */ |
| transient final IdReadWriteLock<Long> offsetLock; |
| |
| private final NavigableSet<BlockCacheKey> blocksByHFile = new ConcurrentSkipListSet<>((a, b) -> { |
| int nameComparison = a.getHfileName().compareTo(b.getHfileName()); |
| if (nameComparison != 0) { |
| return nameComparison; |
| } |
| return Long.compare(a.getOffset(), b.getOffset()); |
| }); |
| |
| /** Statistics thread schedule pool (for heavy debugging, could remove) */ |
| private transient final ScheduledExecutorService scheduleThreadPool = |
| Executors.newScheduledThreadPool(1, |
| new ThreadFactoryBuilder().setNameFormat("BucketCacheStatsExecutor").setDaemon(true).build()); |
| |
| // Allocate or free space for the block |
| private transient BucketAllocator bucketAllocator; |
| |
| /** Acceptable size of cache (no evictions if size < acceptable) */ |
| private float acceptableFactor; |
| |
| /** Minimum threshold of cache (when evicting, evict until size < min) */ |
| private float minFactor; |
| |
| /** Free this floating point factor of extra blocks when evicting. For example free the number of blocks requested * (1 + extraFreeFactor) */ |
| private float extraFreeFactor; |
| |
| /** Single access bucket size */ |
| private float singleFactor; |
| |
| /** Multiple access bucket size */ |
| private float multiFactor; |
| |
| /** In-memory bucket size */ |
| private float memoryFactor; |
| |
| private static final String FILE_VERIFY_ALGORITHM = |
| "hbase.bucketcache.persistent.file.integrity.check.algorithm"; |
| private static final String DEFAULT_FILE_VERIFY_ALGORITHM = "MD5"; |
| |
| /** |
| * Use {@link java.security.MessageDigest} class's encryption algorithms to check |
| * persistent file integrity, default algorithm is MD5 |
| * */ |
| private String algorithm; |
| |
| public BucketCache(String ioEngineName, long capacity, int blockSize, int[] bucketSizes, |
| int writerThreadNum, int writerQLen, String persistencePath) throws IOException { |
| this(ioEngineName, capacity, blockSize, bucketSizes, writerThreadNum, writerQLen, |
| persistencePath, DEFAULT_ERROR_TOLERATION_DURATION, HBaseConfiguration.create()); |
| } |
| |
| public BucketCache(String ioEngineName, long capacity, int blockSize, int[] bucketSizes, |
| int writerThreadNum, int writerQLen, String persistencePath, int ioErrorsTolerationDuration, |
| Configuration conf) throws IOException { |
| boolean useStrongRef = conf.getBoolean(STRONG_REF_KEY, STRONG_REF_DEFAULT); |
| if (useStrongRef) { |
| this.offsetLock = new IdReadWriteLockStrongRef<>(); |
| } else { |
| this.offsetLock = new IdReadWriteLockWithObjectPool<>(ReferenceType.SOFT); |
| } |
| this.algorithm = conf.get(FILE_VERIFY_ALGORITHM, DEFAULT_FILE_VERIFY_ALGORITHM); |
| this.ioEngine = getIOEngineFromName(ioEngineName, capacity, persistencePath); |
| this.writerThreads = new WriterThread[writerThreadNum]; |
| long blockNumCapacity = capacity / blockSize; |
| if (blockNumCapacity >= Integer.MAX_VALUE) { |
| // Enough for about 32TB of cache! |
| throw new IllegalArgumentException("Cache capacity is too large, only support 32TB now"); |
| } |
| |
| this.acceptableFactor = conf.getFloat(ACCEPT_FACTOR_CONFIG_NAME, DEFAULT_ACCEPT_FACTOR); |
| this.minFactor = conf.getFloat(MIN_FACTOR_CONFIG_NAME, DEFAULT_MIN_FACTOR); |
| this.extraFreeFactor = conf.getFloat(EXTRA_FREE_FACTOR_CONFIG_NAME, DEFAULT_EXTRA_FREE_FACTOR); |
| this.singleFactor = conf.getFloat(SINGLE_FACTOR_CONFIG_NAME, DEFAULT_SINGLE_FACTOR); |
| this.multiFactor = conf.getFloat(MULTI_FACTOR_CONFIG_NAME, DEFAULT_MULTI_FACTOR); |
| this.memoryFactor = conf.getFloat(MEMORY_FACTOR_CONFIG_NAME, DEFAULT_MEMORY_FACTOR); |
| |
| sanityCheckConfigs(); |
| |
| LOG.info("Instantiating BucketCache with acceptableFactor: " + acceptableFactor + ", minFactor: " + minFactor + |
| ", extraFreeFactor: " + extraFreeFactor + ", singleFactor: " + singleFactor + ", multiFactor: " + multiFactor + |
| ", memoryFactor: " + memoryFactor + ", useStrongRef: " + useStrongRef); |
| |
| this.cacheCapacity = capacity; |
| this.persistencePath = persistencePath; |
| this.blockSize = blockSize; |
| this.ioErrorsTolerationDuration = ioErrorsTolerationDuration; |
| |
| bucketAllocator = new BucketAllocator(capacity, bucketSizes); |
| for (int i = 0; i < writerThreads.length; ++i) { |
| writerQueues.add(new ArrayBlockingQueue<>(writerQLen)); |
| } |
| |
| assert writerQueues.size() == writerThreads.length; |
| this.ramCache = new RAMCache(); |
| |
| this.backingMap = new ConcurrentHashMap<>((int) blockNumCapacity); |
| |
| if (ioEngine.isPersistent() && persistencePath != null) { |
| try { |
| retrieveFromFile(bucketSizes); |
| } catch (IOException ioex) { |
| LOG.error("Can't restore from file[" + persistencePath + "] because of ", ioex); |
| } |
| } |
| final String threadName = Thread.currentThread().getName(); |
| this.cacheEnabled = true; |
| for (int i = 0; i < writerThreads.length; ++i) { |
| writerThreads[i] = new WriterThread(writerQueues.get(i)); |
| writerThreads[i].setName(threadName + "-BucketCacheWriter-" + i); |
| writerThreads[i].setDaemon(true); |
| } |
| startWriterThreads(); |
| |
| // Run the statistics thread periodically to print the cache statistics log |
| // TODO: Add means of turning this off. Bit obnoxious running thread just to make a log |
| // every five minutes. |
| this.scheduleThreadPool.scheduleAtFixedRate(new StatisticsThread(this), |
| statThreadPeriod, statThreadPeriod, TimeUnit.SECONDS); |
| LOG.info("Started bucket cache; ioengine=" + ioEngineName + |
| ", capacity=" + StringUtils.byteDesc(capacity) + |
| ", blockSize=" + StringUtils.byteDesc(blockSize) + ", writerThreadNum=" + |
| writerThreadNum + ", writerQLen=" + writerQLen + ", persistencePath=" + |
| persistencePath + ", bucketAllocator=" + this.bucketAllocator.getClass().getName()); |
| } |
| |
| private void sanityCheckConfigs() { |
| Preconditions.checkArgument(acceptableFactor <= 1 && acceptableFactor >= 0, ACCEPT_FACTOR_CONFIG_NAME + " must be between 0.0 and 1.0"); |
| Preconditions.checkArgument(minFactor <= 1 && minFactor >= 0, MIN_FACTOR_CONFIG_NAME + " must be between 0.0 and 1.0"); |
| Preconditions.checkArgument(minFactor <= acceptableFactor, MIN_FACTOR_CONFIG_NAME + " must be <= " + ACCEPT_FACTOR_CONFIG_NAME); |
| Preconditions.checkArgument(extraFreeFactor >= 0, EXTRA_FREE_FACTOR_CONFIG_NAME + " must be greater than 0.0"); |
| Preconditions.checkArgument(singleFactor <= 1 && singleFactor >= 0, SINGLE_FACTOR_CONFIG_NAME + " must be between 0.0 and 1.0"); |
| Preconditions.checkArgument(multiFactor <= 1 && multiFactor >= 0, MULTI_FACTOR_CONFIG_NAME + " must be between 0.0 and 1.0"); |
| Preconditions.checkArgument(memoryFactor <= 1 && memoryFactor >= 0, MEMORY_FACTOR_CONFIG_NAME + " must be between 0.0 and 1.0"); |
| Preconditions.checkArgument((singleFactor + multiFactor + memoryFactor) == 1, SINGLE_FACTOR_CONFIG_NAME + ", " + |
| MULTI_FACTOR_CONFIG_NAME + ", and " + MEMORY_FACTOR_CONFIG_NAME + " segments must add up to 1.0"); |
| } |
| |
| /** |
| * Called by the constructor to start the writer threads. Used by tests that need to override |
| * starting the threads. |
| */ |
| protected void startWriterThreads() { |
| for (WriterThread thread : writerThreads) { |
| thread.start(); |
| } |
| } |
| |
| boolean isCacheEnabled() { |
| return this.cacheEnabled; |
| } |
| |
| @Override |
| public long getMaxSize() { |
| return this.cacheCapacity; |
| } |
| |
| public String getIoEngine() { |
| return ioEngine.toString(); |
| } |
| |
| /** |
| * Get the IOEngine from the IO engine name |
| * @param ioEngineName |
| * @param capacity |
| * @param persistencePath |
| * @return the IOEngine |
| * @throws IOException |
| */ |
| private IOEngine getIOEngineFromName(String ioEngineName, long capacity, String persistencePath) |
| throws IOException { |
| if (ioEngineName.startsWith("file:") || ioEngineName.startsWith("files:")) { |
| // In order to make the usage simple, we only need the prefix 'files:' in |
| // document whether one or multiple file(s), but also support 'file:' for |
| // the compatibility |
| String[] filePaths = ioEngineName.substring(ioEngineName.indexOf(":") + 1) |
| .split(FileIOEngine.FILE_DELIMITER); |
| return new FileIOEngine(capacity, persistencePath != null, filePaths); |
| } else if (ioEngineName.startsWith("offheap")) { |
| return new ByteBufferIOEngine(capacity); |
| } else if (ioEngineName.startsWith("mmap:")) { |
| return new ExclusiveMemoryMmapIOEngine(ioEngineName.substring(5), capacity); |
| } else if (ioEngineName.startsWith("pmem:")) { |
| // This mode of bucket cache creates an IOEngine over a file on the persistent memory |
| // device. Since the persistent memory device has its own address space the contents |
| // mapped to this address space does not get swapped out like in the case of mmapping |
| // on to DRAM. Hence the cells created out of the hfile blocks in the pmem bucket cache |
| // can be directly referred to without having to copy them onheap. Once the RPC is done, |
| // the blocks can be returned back as in case of ByteBufferIOEngine. |
| return new SharedMemoryMmapIOEngine(ioEngineName.substring(5), capacity); |
| } else { |
| throw new IllegalArgumentException( |
| "Don't understand io engine name for cache- prefix with file:, files:, mmap: or offheap"); |
| } |
| } |
| |
| /** |
| * Cache the block with the specified name and buffer. |
| * @param cacheKey block's cache key |
| * @param buf block buffer |
| */ |
| @Override |
| public void cacheBlock(BlockCacheKey cacheKey, Cacheable buf) { |
| cacheBlock(cacheKey, buf, false); |
| } |
| |
| /** |
| * Cache the block with the specified name and buffer. |
| * @param cacheKey block's cache key |
| * @param cachedItem block buffer |
| * @param inMemory if block is in-memory |
| */ |
| @Override |
| public void cacheBlock(BlockCacheKey cacheKey, Cacheable cachedItem, boolean inMemory) { |
| cacheBlockWithWait(cacheKey, cachedItem, inMemory, wait_when_cache); |
| } |
| |
| /** |
| * Cache the block to ramCache |
| * @param cacheKey block's cache key |
| * @param cachedItem block buffer |
| * @param inMemory if block is in-memory |
| * @param wait if true, blocking wait when queue is full |
| */ |
| public void cacheBlockWithWait(BlockCacheKey cacheKey, Cacheable cachedItem, boolean inMemory, |
| boolean wait) { |
| if (cacheEnabled) { |
| if (backingMap.containsKey(cacheKey) || ramCache.containsKey(cacheKey)) { |
| if (BlockCacheUtil.shouldReplaceExistingCacheBlock(this, cacheKey, cachedItem)) { |
| cacheBlockWithWaitInternal(cacheKey, cachedItem, inMemory, wait); |
| } |
| } else { |
| cacheBlockWithWaitInternal(cacheKey, cachedItem, inMemory, wait); |
| } |
| } |
| } |
| |
| private void cacheBlockWithWaitInternal(BlockCacheKey cacheKey, Cacheable cachedItem, |
| boolean inMemory, boolean wait) { |
| if (!cacheEnabled) { |
| return; |
| } |
| LOG.trace("Caching key={}, item={}", cacheKey, cachedItem); |
| // Stuff the entry into the RAM cache so it can get drained to the persistent store |
| RAMQueueEntry re = |
| new RAMQueueEntry(cacheKey, cachedItem, accessCount.incrementAndGet(), inMemory, |
| createRecycler(cacheKey)); |
| /** |
| * Don't use ramCache.put(cacheKey, re) here. because there may be a existing entry with same |
| * key in ramCache, the heap size of bucket cache need to update if replacing entry from |
| * ramCache. But WriterThread will also remove entry from ramCache and update heap size, if |
| * using ramCache.put(), It's possible that the removed entry in WriterThread is not the correct |
| * one, then the heap size will mess up (HBASE-20789) |
| */ |
| if (ramCache.putIfAbsent(cacheKey, re) != null) { |
| return; |
| } |
| int queueNum = (cacheKey.hashCode() & 0x7FFFFFFF) % writerQueues.size(); |
| BlockingQueue<RAMQueueEntry> bq = writerQueues.get(queueNum); |
| boolean successfulAddition = false; |
| if (wait) { |
| try { |
| successfulAddition = bq.offer(re, DEFAULT_CACHE_WAIT_TIME, TimeUnit.MILLISECONDS); |
| } catch (InterruptedException e) { |
| Thread.currentThread().interrupt(); |
| } |
| } else { |
| successfulAddition = bq.offer(re); |
| } |
| if (!successfulAddition) { |
| ramCache.remove(cacheKey); |
| cacheStats.failInsert(); |
| } else { |
| this.blockNumber.increment(); |
| this.heapSize.add(cachedItem.heapSize()); |
| blocksByHFile.add(cacheKey); |
| } |
| } |
| |
| /** |
| * Get the buffer of the block with the specified key. |
| * @param key block's cache key |
| * @param caching true if the caller caches blocks on cache misses |
| * @param repeat Whether this is a repeat lookup for the same block |
| * @param updateCacheMetrics Whether we should update cache metrics or not |
| * @return buffer of specified cache key, or null if not in cache |
| */ |
| @Override |
| public Cacheable getBlock(BlockCacheKey key, boolean caching, boolean repeat, |
| boolean updateCacheMetrics) { |
| if (!cacheEnabled) { |
| return null; |
| } |
| RAMQueueEntry re = ramCache.get(key); |
| if (re != null) { |
| if (updateCacheMetrics) { |
| cacheStats.hit(caching, key.isPrimary(), key.getBlockType()); |
| } |
| re.access(accessCount.incrementAndGet()); |
| return re.getData(); |
| } |
| BucketEntry bucketEntry = backingMap.get(key); |
| if (bucketEntry != null) { |
| long start = System.nanoTime(); |
| ReentrantReadWriteLock lock = offsetLock.getLock(bucketEntry.offset()); |
| try { |
| lock.readLock().lock(); |
| // We can not read here even if backingMap does contain the given key because its offset |
| // maybe changed. If we lock BlockCacheKey instead of offset, then we can only check |
| // existence here. |
| if (bucketEntry.equals(backingMap.get(key))) { |
| // Read the block from IOEngine based on the bucketEntry's offset and length, NOTICE: the |
| // block will use the refCnt of bucketEntry, which means if two HFileBlock mapping to |
| // the same BucketEntry, then all of the three will share the same refCnt. |
| Cacheable cachedBlock = ioEngine.read(bucketEntry); |
| if (ioEngine.usesSharedMemory()) { |
| // If IOEngine use shared memory, cachedBlock and BucketEntry will share the |
| // same RefCnt, do retain here, in order to count the number of RPC references |
| cachedBlock.retain(); |
| } |
| // Update the cache statistics. |
| if (updateCacheMetrics) { |
| cacheStats.hit(caching, key.isPrimary(), key.getBlockType()); |
| cacheStats.ioHit(System.nanoTime() - start); |
| } |
| bucketEntry.access(accessCount.incrementAndGet()); |
| if (this.ioErrorStartTime > 0) { |
| ioErrorStartTime = -1; |
| } |
| return cachedBlock; |
| } |
| } catch (IOException ioex) { |
| LOG.error("Failed reading block " + key + " from bucket cache", ioex); |
| checkIOErrorIsTolerated(); |
| } finally { |
| lock.readLock().unlock(); |
| } |
| } |
| if (!repeat && updateCacheMetrics) { |
| cacheStats.miss(caching, key.isPrimary(), key.getBlockType()); |
| } |
| return null; |
| } |
| |
| void blockEvicted(BlockCacheKey cacheKey, BucketEntry bucketEntry, boolean decrementBlockNumber) { |
| bucketAllocator.freeBlock(bucketEntry.offset()); |
| realCacheSize.add(-1 * bucketEntry.getLength()); |
| blocksByHFile.remove(cacheKey); |
| if (decrementBlockNumber) { |
| this.blockNumber.decrement(); |
| } |
| } |
| |
| /** |
| * Try to evict the block from {@link BlockCache} by force. We'll call this in few cases:<br> |
| * 1. Close an HFile, and clear all cached blocks. <br> |
| * 2. Call {@link Admin#clearBlockCache(TableName)} to clear all blocks for a given table.<br> |
| * <p> |
| * Firstly, we'll try to remove the block from RAMCache. If it doesn't exist in RAMCache, then try |
| * to evict from backingMap. Here we only need to free the reference from bucket cache by calling |
| * {@link BucketEntry#markedAsEvicted}. If there're still some RPC referring this block, block can |
| * only be de-allocated when all of them release the block. |
| * <p> |
| * NOTICE: we need to grab the write offset lock firstly before releasing the reference from |
| * bucket cache. if we don't, we may read an {@link BucketEntry} with refCnt = 0 when |
| * {@link BucketCache#getBlock(BlockCacheKey, boolean, boolean, boolean)}, it's a memory leak. |
| * @param cacheKey Block to evict |
| * @return true to indicate whether we've evicted successfully or not. |
| */ |
| @Override |
| public boolean evictBlock(BlockCacheKey cacheKey) { |
| if (!cacheEnabled) { |
| return false; |
| } |
| boolean existed = removeFromRamCache(cacheKey); |
| BucketEntry be = backingMap.get(cacheKey); |
| if (be == null) { |
| if (existed) { |
| cacheStats.evicted(0, cacheKey.isPrimary()); |
| } |
| return existed; |
| } else { |
| return be.withWriteLock(offsetLock, be::markAsEvicted); |
| } |
| } |
| |
| private Recycler createRecycler(BlockCacheKey cacheKey) { |
| return () -> { |
| if (!cacheEnabled) { |
| return; |
| } |
| boolean existed = removeFromRamCache(cacheKey); |
| BucketEntry be = backingMap.get(cacheKey); |
| if (be == null && existed) { |
| cacheStats.evicted(0, cacheKey.isPrimary()); |
| } else if (be != null) { |
| be.withWriteLock(offsetLock, () -> { |
| if (backingMap.remove(cacheKey, be)) { |
| blockEvicted(cacheKey, be, !existed); |
| cacheStats.evicted(be.getCachedTime(), cacheKey.isPrimary()); |
| } |
| return null; |
| }); |
| } |
| }; |
| } |
| |
| private boolean removeFromRamCache(BlockCacheKey cacheKey) { |
| return ramCache.remove(cacheKey, re -> { |
| if (re != null) { |
| this.blockNumber.decrement(); |
| this.heapSize.add(-1 * re.getData().heapSize()); |
| } |
| }); |
| } |
| |
| /* |
| * Statistics thread. Periodically output cache statistics to the log. |
| */ |
| private static class StatisticsThread extends Thread { |
| private final BucketCache bucketCache; |
| |
| public StatisticsThread(BucketCache bucketCache) { |
| super("BucketCacheStatsThread"); |
| setDaemon(true); |
| this.bucketCache = bucketCache; |
| } |
| |
| @Override |
| public void run() { |
| bucketCache.logStats(); |
| } |
| } |
| |
| public void logStats() { |
| long totalSize = bucketAllocator.getTotalSize(); |
| long usedSize = bucketAllocator.getUsedSize(); |
| long freeSize = totalSize - usedSize; |
| long cacheSize = getRealCacheSize(); |
| LOG.info("failedBlockAdditions=" + cacheStats.getFailedInserts() + ", " + |
| "totalSize=" + StringUtils.byteDesc(totalSize) + ", " + |
| "freeSize=" + StringUtils.byteDesc(freeSize) + ", " + |
| "usedSize=" + StringUtils.byteDesc(usedSize) +", " + |
| "cacheSize=" + StringUtils.byteDesc(cacheSize) +", " + |
| "accesses=" + cacheStats.getRequestCount() + ", " + |
| "hits=" + cacheStats.getHitCount() + ", " + |
| "IOhitsPerSecond=" + cacheStats.getIOHitsPerSecond() + ", " + |
| "IOTimePerHit=" + String.format("%.2f", cacheStats.getIOTimePerHit())+ ", " + |
| "hitRatio=" + (cacheStats.getHitCount() == 0 ? "0," : |
| (StringUtils.formatPercent(cacheStats.getHitRatio(), 2)+ ", ")) + |
| "cachingAccesses=" + cacheStats.getRequestCachingCount() + ", " + |
| "cachingHits=" + cacheStats.getHitCachingCount() + ", " + |
| "cachingHitsRatio=" +(cacheStats.getHitCachingCount() == 0 ? "0," : |
| (StringUtils.formatPercent(cacheStats.getHitCachingRatio(), 2)+ ", ")) + |
| "evictions=" + cacheStats.getEvictionCount() + ", " + |
| "evicted=" + cacheStats.getEvictedCount() + ", " + |
| "evictedPerRun=" + cacheStats.evictedPerEviction()); |
| cacheStats.reset(); |
| } |
| |
| public long getRealCacheSize() { |
| return this.realCacheSize.sum(); |
| } |
| |
| public long acceptableSize() { |
| return (long) Math.floor(bucketAllocator.getTotalSize() * acceptableFactor); |
| } |
| |
| long getPartitionSize(float partitionFactor) { |
| return (long) Math.floor(bucketAllocator.getTotalSize() * partitionFactor * minFactor); |
| } |
| |
| /** |
| * Return the count of bucketSizeinfos still need free space |
| */ |
| private int bucketSizesAboveThresholdCount(float minFactor) { |
| BucketAllocator.IndexStatistics[] stats = bucketAllocator.getIndexStatistics(); |
| int fullCount = 0; |
| for (int i = 0; i < stats.length; i++) { |
| long freeGoal = (long) Math.floor(stats[i].totalCount() * (1 - minFactor)); |
| freeGoal = Math.max(freeGoal, 1); |
| if (stats[i].freeCount() < freeGoal) { |
| fullCount++; |
| } |
| } |
| return fullCount; |
| } |
| |
| /** |
| * This method will find the buckets that are minimally occupied |
| * and are not reference counted and will free them completely |
| * without any constraint on the access times of the elements, |
| * and as a process will completely free at most the number of buckets |
| * passed, sometimes it might not due to changing refCounts |
| * |
| * @param completelyFreeBucketsNeeded number of buckets to free |
| **/ |
| private void freeEntireBuckets(int completelyFreeBucketsNeeded) { |
| if (completelyFreeBucketsNeeded != 0) { |
| // First we will build a set where the offsets are reference counted, usually |
| // this set is small around O(Handler Count) unless something else is wrong |
| Set<Integer> inUseBuckets = new HashSet<>(); |
| backingMap.forEach((k, be) -> { |
| if (be.isRpcRef()) { |
| inUseBuckets.add(bucketAllocator.getBucketIndex(be.offset())); |
| } |
| }); |
| Set<Integer> candidateBuckets = |
| bucketAllocator.getLeastFilledBuckets(inUseBuckets, completelyFreeBucketsNeeded); |
| for (Map.Entry<BlockCacheKey, BucketEntry> entry : backingMap.entrySet()) { |
| if (candidateBuckets.contains(bucketAllocator.getBucketIndex(entry.getValue().offset()))) { |
| entry.getValue().withWriteLock(offsetLock, entry.getValue()::markStaleAsEvicted); |
| } |
| } |
| } |
| } |
| |
| /** |
| * Free the space if the used size reaches acceptableSize() or one size block |
| * couldn't be allocated. When freeing the space, we use the LRU algorithm and |
| * ensure there must be some blocks evicted |
| * @param why Why we are being called |
| */ |
| private void freeSpace(final String why) { |
| // Ensure only one freeSpace progress at a time |
| if (!freeSpaceLock.tryLock()) { |
| return; |
| } |
| try { |
| freeInProgress = true; |
| long bytesToFreeWithoutExtra = 0; |
| // Calculate free byte for each bucketSizeinfo |
| StringBuilder msgBuffer = LOG.isDebugEnabled()? new StringBuilder(): null; |
| BucketAllocator.IndexStatistics[] stats = bucketAllocator.getIndexStatistics(); |
| long[] bytesToFreeForBucket = new long[stats.length]; |
| for (int i = 0; i < stats.length; i++) { |
| bytesToFreeForBucket[i] = 0; |
| long freeGoal = (long) Math.floor(stats[i].totalCount() * (1 - minFactor)); |
| freeGoal = Math.max(freeGoal, 1); |
| if (stats[i].freeCount() < freeGoal) { |
| bytesToFreeForBucket[i] = stats[i].itemSize() * (freeGoal - stats[i].freeCount()); |
| bytesToFreeWithoutExtra += bytesToFreeForBucket[i]; |
| if (msgBuffer != null) { |
| msgBuffer.append("Free for bucketSize(" + stats[i].itemSize() + ")=" |
| + StringUtils.byteDesc(bytesToFreeForBucket[i]) + ", "); |
| } |
| } |
| } |
| if (msgBuffer != null) { |
| msgBuffer.append("Free for total=" + StringUtils.byteDesc(bytesToFreeWithoutExtra) + ", "); |
| } |
| |
| if (bytesToFreeWithoutExtra <= 0) { |
| return; |
| } |
| long currentSize = bucketAllocator.getUsedSize(); |
| long totalSize = bucketAllocator.getTotalSize(); |
| if (LOG.isDebugEnabled() && msgBuffer != null) { |
| LOG.debug("Free started because \"" + why + "\"; " + msgBuffer.toString() + |
| " of current used=" + StringUtils.byteDesc(currentSize) + ", actual cacheSize=" + |
| StringUtils.byteDesc(realCacheSize.sum()) + ", total=" + StringUtils.byteDesc(totalSize)); |
| } |
| |
| long bytesToFreeWithExtra = (long) Math.floor(bytesToFreeWithoutExtra |
| * (1 + extraFreeFactor)); |
| |
| // Instantiate priority buckets |
| BucketEntryGroup bucketSingle = new BucketEntryGroup(bytesToFreeWithExtra, |
| blockSize, getPartitionSize(singleFactor)); |
| BucketEntryGroup bucketMulti = new BucketEntryGroup(bytesToFreeWithExtra, |
| blockSize, getPartitionSize(multiFactor)); |
| BucketEntryGroup bucketMemory = new BucketEntryGroup(bytesToFreeWithExtra, |
| blockSize, getPartitionSize(memoryFactor)); |
| |
| // Scan entire map putting bucket entry into appropriate bucket entry |
| // group |
| for (Map.Entry<BlockCacheKey, BucketEntry> bucketEntryWithKey : backingMap.entrySet()) { |
| switch (bucketEntryWithKey.getValue().getPriority()) { |
| case SINGLE: { |
| bucketSingle.add(bucketEntryWithKey); |
| break; |
| } |
| case MULTI: { |
| bucketMulti.add(bucketEntryWithKey); |
| break; |
| } |
| case MEMORY: { |
| bucketMemory.add(bucketEntryWithKey); |
| break; |
| } |
| } |
| } |
| |
| PriorityQueue<BucketEntryGroup> bucketQueue = new PriorityQueue<>(3, |
| Comparator.comparingLong(BucketEntryGroup::overflow)); |
| |
| bucketQueue.add(bucketSingle); |
| bucketQueue.add(bucketMulti); |
| bucketQueue.add(bucketMemory); |
| |
| int remainingBuckets = bucketQueue.size(); |
| long bytesFreed = 0; |
| |
| BucketEntryGroup bucketGroup; |
| while ((bucketGroup = bucketQueue.poll()) != null) { |
| long overflow = bucketGroup.overflow(); |
| if (overflow > 0) { |
| long bucketBytesToFree = Math.min(overflow, |
| (bytesToFreeWithoutExtra - bytesFreed) / remainingBuckets); |
| bytesFreed += bucketGroup.free(bucketBytesToFree); |
| } |
| remainingBuckets--; |
| } |
| |
| // Check and free if there are buckets that still need freeing of space |
| if (bucketSizesAboveThresholdCount(minFactor) > 0) { |
| bucketQueue.clear(); |
| remainingBuckets = 3; |
| |
| bucketQueue.add(bucketSingle); |
| bucketQueue.add(bucketMulti); |
| bucketQueue.add(bucketMemory); |
| |
| while ((bucketGroup = bucketQueue.poll()) != null) { |
| long bucketBytesToFree = (bytesToFreeWithExtra - bytesFreed) / remainingBuckets; |
| bytesFreed += bucketGroup.free(bucketBytesToFree); |
| remainingBuckets--; |
| } |
| } |
| |
| // Even after the above free we might still need freeing because of the |
| // De-fragmentation of the buckets (also called Slab Calcification problem), i.e |
| // there might be some buckets where the occupancy is very sparse and thus are not |
| // yielding the free for the other bucket sizes, the fix for this to evict some |
| // of the buckets, we do this by evicting the buckets that are least fulled |
| freeEntireBuckets(DEFAULT_FREE_ENTIRE_BLOCK_FACTOR * |
| bucketSizesAboveThresholdCount(1.0f)); |
| |
| if (LOG.isDebugEnabled()) { |
| long single = bucketSingle.totalSize(); |
| long multi = bucketMulti.totalSize(); |
| long memory = bucketMemory.totalSize(); |
| if (LOG.isDebugEnabled()) { |
| LOG.debug("Bucket cache free space completed; " + "freed=" |
| + StringUtils.byteDesc(bytesFreed) + ", " + "total=" |
| + StringUtils.byteDesc(totalSize) + ", " + "single=" |
| + StringUtils.byteDesc(single) + ", " + "multi=" |
| + StringUtils.byteDesc(multi) + ", " + "memory=" |
| + StringUtils.byteDesc(memory)); |
| } |
| } |
| |
| } catch (Throwable t) { |
| LOG.warn("Failed freeing space", t); |
| } finally { |
| cacheStats.evict(); |
| freeInProgress = false; |
| freeSpaceLock.unlock(); |
| } |
| } |
| |
| // This handles flushing the RAM cache to IOEngine. |
| class WriterThread extends Thread { |
| private final BlockingQueue<RAMQueueEntry> inputQueue; |
| private volatile boolean writerEnabled = true; |
| |
| WriterThread(BlockingQueue<RAMQueueEntry> queue) { |
| super("BucketCacheWriterThread"); |
| this.inputQueue = queue; |
| } |
| |
| // Used for test |
| void disableWriter() { |
| this.writerEnabled = false; |
| } |
| |
| @Override |
| public void run() { |
| List<RAMQueueEntry> entries = new ArrayList<>(); |
| try { |
| while (cacheEnabled && writerEnabled) { |
| try { |
| try { |
| // Blocks |
| entries = getRAMQueueEntries(inputQueue, entries); |
| } catch (InterruptedException ie) { |
| if (!cacheEnabled || !writerEnabled) { |
| break; |
| } |
| } |
| doDrain(entries); |
| } catch (Exception ioe) { |
| LOG.error("WriterThread encountered error", ioe); |
| } |
| } |
| } catch (Throwable t) { |
| LOG.warn("Failed doing drain", t); |
| } |
| LOG.info(this.getName() + " exiting, cacheEnabled=" + cacheEnabled); |
| } |
| |
| /** |
| * Put the new bucket entry into backingMap. Notice that we are allowed to replace the existing |
| * cache with a new block for the same cache key. there's a corner case: one thread cache a |
| * block in ramCache, copy to io-engine and add a bucket entry to backingMap. Caching another |
| * new block with the same cache key do the same thing for the same cache key, so if not evict |
| * the previous bucket entry, then memory leak happen because the previous bucketEntry is gone |
| * but the bucketAllocator do not free its memory. |
| * @see BlockCacheUtil#shouldReplaceExistingCacheBlock(BlockCache blockCache,BlockCacheKey |
| * cacheKey, Cacheable newBlock) |
| * @param key Block cache key |
| * @param bucketEntry Bucket entry to put into backingMap. |
| */ |
| private void putIntoBackingMap(BlockCacheKey key, BucketEntry bucketEntry) { |
| BucketEntry previousEntry = backingMap.put(key, bucketEntry); |
| if (previousEntry != null && previousEntry != bucketEntry) { |
| previousEntry.withWriteLock(offsetLock, () -> { |
| blockEvicted(key, previousEntry, false); |
| return null; |
| }); |
| } |
| } |
| |
| /** |
| * Flush the entries in ramCache to IOEngine and add bucket entry to backingMap. |
| * Process all that are passed in even if failure being sure to remove from ramCache else we'll |
| * never undo the references and we'll OOME. |
| * @param entries Presumes list passed in here will be processed by this invocation only. No |
| * interference expected. |
| * @throws InterruptedException |
| */ |
| void doDrain(final List<RAMQueueEntry> entries) throws InterruptedException { |
| if (entries.isEmpty()) { |
| return; |
| } |
| // This method is a little hard to follow. We run through the passed in entries and for each |
| // successful add, we add a non-null BucketEntry to the below bucketEntries. Later we must |
| // do cleanup making sure we've cleared ramCache of all entries regardless of whether we |
| // successfully added the item to the bucketcache; if we don't do the cleanup, we'll OOME by |
| // filling ramCache. We do the clean up by again running through the passed in entries |
| // doing extra work when we find a non-null bucketEntries corresponding entry. |
| final int size = entries.size(); |
| BucketEntry[] bucketEntries = new BucketEntry[size]; |
| // Index updated inside loop if success or if we can't succeed. We retry if cache is full |
| // when we go to add an entry by going around the loop again without upping the index. |
| int index = 0; |
| while (cacheEnabled && index < size) { |
| RAMQueueEntry re = null; |
| try { |
| re = entries.get(index); |
| if (re == null) { |
| LOG.warn("Couldn't get entry or changed on us; who else is messing with it?"); |
| index++; |
| continue; |
| } |
| BucketEntry bucketEntry = re.writeToCache(ioEngine, bucketAllocator, realCacheSize); |
| // Successfully added. Up index and add bucketEntry. Clear io exceptions. |
| bucketEntries[index] = bucketEntry; |
| if (ioErrorStartTime > 0) { |
| ioErrorStartTime = -1; |
| } |
| index++; |
| } catch (BucketAllocatorException fle) { |
| LOG.warn("Failed allocation for " + (re == null ? "" : re.getKey()) + "; " + fle); |
| // Presume can't add. Too big? Move index on. Entry will be cleared from ramCache below. |
| bucketEntries[index] = null; |
| index++; |
| } catch (CacheFullException cfe) { |
| // Cache full when we tried to add. Try freeing space and then retrying (don't up index) |
| if (!freeInProgress) { |
| freeSpace("Full!"); |
| } else { |
| Thread.sleep(50); |
| } |
| } catch (IOException ioex) { |
| // Hopefully transient. Retry. checkIOErrorIsTolerated disables cache if problem. |
| LOG.error("Failed writing to bucket cache", ioex); |
| checkIOErrorIsTolerated(); |
| } |
| } |
| |
| // Make sure data pages are written on media before we update maps. |
| try { |
| ioEngine.sync(); |
| } catch (IOException ioex) { |
| LOG.error("Failed syncing IO engine", ioex); |
| checkIOErrorIsTolerated(); |
| // Since we failed sync, free the blocks in bucket allocator |
| for (int i = 0; i < entries.size(); ++i) { |
| if (bucketEntries[i] != null) { |
| bucketAllocator.freeBlock(bucketEntries[i].offset()); |
| bucketEntries[i] = null; |
| } |
| } |
| } |
| |
| // Now add to backingMap if successfully added to bucket cache. Remove from ramCache if |
| // success or error. |
| for (int i = 0; i < size; ++i) { |
| BlockCacheKey key = entries.get(i).getKey(); |
| // Only add if non-null entry. |
| if (bucketEntries[i] != null) { |
| putIntoBackingMap(key, bucketEntries[i]); |
| } |
| // Always remove from ramCache even if we failed adding it to the block cache above. |
| boolean existed = ramCache.remove(key, re -> { |
| if (re != null) { |
| heapSize.add(-1 * re.getData().heapSize()); |
| } |
| }); |
| if (!existed && bucketEntries[i] != null) { |
| // Block should have already been evicted. Remove it and free space. |
| final BucketEntry bucketEntry = bucketEntries[i]; |
| bucketEntry.withWriteLock(offsetLock, () -> { |
| if (backingMap.remove(key, bucketEntry)) { |
| blockEvicted(key, bucketEntry, false); |
| } |
| return null; |
| }); |
| } |
| } |
| |
| long used = bucketAllocator.getUsedSize(); |
| if (used > acceptableSize()) { |
| freeSpace("Used=" + used + " > acceptable=" + acceptableSize()); |
| } |
| return; |
| } |
| } |
| |
| /** |
| * Blocks until elements available in {@code q} then tries to grab as many as possible before |
| * returning. |
| * @param receptacle Where to stash the elements taken from queue. We clear before we use it just |
| * in case. |
| * @param q The queue to take from. |
| * @return {@code receptacle} laden with elements taken from the queue or empty if none found. |
| */ |
| static List<RAMQueueEntry> getRAMQueueEntries(BlockingQueue<RAMQueueEntry> q, |
| List<RAMQueueEntry> receptacle) throws InterruptedException { |
| // Clear sets all entries to null and sets size to 0. We retain allocations. Presume it |
| // ok even if list grew to accommodate thousands. |
| receptacle.clear(); |
| receptacle.add(q.take()); |
| q.drainTo(receptacle); |
| return receptacle; |
| } |
| |
| /** |
| * @see #retrieveFromFile(int[]) |
| */ |
| @edu.umd.cs.findbugs.annotations.SuppressWarnings(value="OBL_UNSATISFIED_OBLIGATION", |
| justification = "false positive, try-with-resources ensures close is called.") |
| private void persistToFile() throws IOException { |
| assert !cacheEnabled; |
| if (!ioEngine.isPersistent()) { |
| throw new IOException("Attempt to persist non-persistent cache mappings!"); |
| } |
| try (FileOutputStream fos = new FileOutputStream(persistencePath, false)) { |
| fos.write(ProtobufMagic.PB_MAGIC); |
| BucketProtoUtils.toPB(this).writeDelimitedTo(fos); |
| } |
| } |
| |
| /** |
| * @see #persistToFile() |
| */ |
| private void retrieveFromFile(int[] bucketSizes) throws IOException { |
| File persistenceFile = new File(persistencePath); |
| if (!persistenceFile.exists()) { |
| return; |
| } |
| assert !cacheEnabled; |
| |
| try (FileInputStream in = deleteFileOnClose(persistenceFile)) { |
| int pblen = ProtobufMagic.lengthOfPBMagic(); |
| byte[] pbuf = new byte[pblen]; |
| int read = in.read(pbuf); |
| if (read != pblen) { |
| throw new IOException("Incorrect number of bytes read while checking for protobuf magic " |
| + "number. Requested=" + pblen + ", Received= " + read + ", File=" + persistencePath); |
| } |
| if (! ProtobufMagic.isPBMagicPrefix(pbuf)) { |
| // In 3.0 we have enough flexibility to dump the old cache data. |
| // TODO: In 2.x line, this might need to be filled in to support reading the old format |
| throw new IOException("Persistence file does not start with protobuf magic number. " + |
| persistencePath); |
| } |
| parsePB(BucketCacheProtos.BucketCacheEntry.parseDelimitedFrom(in)); |
| bucketAllocator = new BucketAllocator(cacheCapacity, bucketSizes, backingMap, realCacheSize); |
| blockNumber.add(backingMap.size()); |
| } |
| } |
| |
| /** |
| * Create an input stream that deletes the file after reading it. Use in try-with-resources to |
| * avoid this pattern where an exception thrown from a finally block may mask earlier exceptions: |
| * <pre> |
| * File f = ... |
| * try (FileInputStream fis = new FileInputStream(f)) { |
| * // use the input stream |
| * } finally { |
| * if (!f.delete()) throw new IOException("failed to delete"); |
| * } |
| * </pre> |
| * @param file the file to read and delete |
| * @return a FileInputStream for the given file |
| * @throws IOException if there is a problem creating the stream |
| */ |
| private FileInputStream deleteFileOnClose(final File file) throws IOException { |
| return new FileInputStream(file) { |
| @Override |
| public void close() throws IOException { |
| super.close(); |
| if (!file.delete()) { |
| throw new IOException("Failed deleting persistence file " + file.getAbsolutePath()); |
| } |
| } |
| }; |
| } |
| |
| private void verifyCapacityAndClasses(long capacitySize, String ioclass, String mapclass) |
| throws IOException { |
| if (capacitySize != cacheCapacity) { |
| throw new IOException("Mismatched cache capacity:" |
| + StringUtils.byteDesc(capacitySize) + ", expected: " |
| + StringUtils.byteDesc(cacheCapacity)); |
| } |
| if (!ioEngine.getClass().getName().equals(ioclass)) { |
| throw new IOException("Class name for IO engine mismatch: " + ioclass |
| + ", expected:" + ioEngine.getClass().getName()); |
| } |
| if (!backingMap.getClass().getName().equals(mapclass)) { |
| throw new IOException("Class name for cache map mismatch: " + mapclass |
| + ", expected:" + backingMap.getClass().getName()); |
| } |
| } |
| |
| private void parsePB(BucketCacheProtos.BucketCacheEntry proto) throws IOException { |
| if (proto.hasChecksum()) { |
| ((PersistentIOEngine) ioEngine).verifyFileIntegrity(proto.getChecksum().toByteArray(), |
| algorithm); |
| } else { |
| // if has not checksum, it means the persistence file is old format |
| LOG.info("Persistent file is old format, it does not support verifying file integrity!"); |
| } |
| verifyCapacityAndClasses(proto.getCacheCapacity(), proto.getIoClass(), proto.getMapClass()); |
| backingMap = BucketProtoUtils.fromPB(proto.getDeserializersMap(), proto.getBackingMap()); |
| } |
| |
| /** |
| * Check whether we tolerate IO error this time. If the duration of IOEngine |
| * throwing errors exceeds ioErrorsDurationTimeTolerated, we will disable the |
| * cache |
| */ |
| private void checkIOErrorIsTolerated() { |
| long now = EnvironmentEdgeManager.currentTime(); |
| // Do a single read to a local variable to avoid timing issue - HBASE-24454 |
| long ioErrorStartTimeTmp = this.ioErrorStartTime; |
| if (ioErrorStartTimeTmp > 0) { |
| if (cacheEnabled && (now - ioErrorStartTimeTmp) > this.ioErrorsTolerationDuration) { |
| LOG.error("IO errors duration time has exceeded " + ioErrorsTolerationDuration + |
| "ms, disabling cache, please check your IOEngine"); |
| disableCache(); |
| } |
| } else { |
| this.ioErrorStartTime = now; |
| } |
| } |
| |
| /** |
| * Used to shut down the cache -or- turn it off in the case of something broken. |
| */ |
| private void disableCache() { |
| if (!cacheEnabled) return; |
| cacheEnabled = false; |
| ioEngine.shutdown(); |
| this.scheduleThreadPool.shutdown(); |
| for (int i = 0; i < writerThreads.length; ++i) writerThreads[i].interrupt(); |
| this.ramCache.clear(); |
| if (!ioEngine.isPersistent() || persistencePath == null) { |
| // If persistent ioengine and a path, we will serialize out the backingMap. |
| this.backingMap.clear(); |
| } |
| } |
| |
| private void join() throws InterruptedException { |
| for (int i = 0; i < writerThreads.length; ++i) |
| writerThreads[i].join(); |
| } |
| |
| @Override |
| public void shutdown() { |
| disableCache(); |
| LOG.info("Shutdown bucket cache: IO persistent=" + ioEngine.isPersistent() |
| + "; path to write=" + persistencePath); |
| if (ioEngine.isPersistent() && persistencePath != null) { |
| try { |
| join(); |
| persistToFile(); |
| } catch (IOException ex) { |
| LOG.error("Unable to persist data on exit: " + ex.toString(), ex); |
| } catch (InterruptedException e) { |
| LOG.warn("Failed to persist data on exit", e); |
| } |
| } |
| } |
| |
| @Override |
| public CacheStats getStats() { |
| return cacheStats; |
| } |
| |
| public BucketAllocator getAllocator() { |
| return this.bucketAllocator; |
| } |
| |
| @Override |
| public long heapSize() { |
| return this.heapSize.sum(); |
| } |
| |
| @Override |
| public long size() { |
| return this.realCacheSize.sum(); |
| } |
| |
| @Override |
| public long getCurrentDataSize() { |
| return size(); |
| } |
| |
| @Override |
| public long getFreeSize() { |
| return this.bucketAllocator.getFreeSize(); |
| } |
| |
| @Override |
| public long getBlockCount() { |
| return this.blockNumber.sum(); |
| } |
| |
| @Override |
| public long getDataBlockCount() { |
| return getBlockCount(); |
| } |
| |
| @Override |
| public long getCurrentSize() { |
| return this.bucketAllocator.getUsedSize(); |
| } |
| |
| protected String getAlgorithm() { |
| return algorithm; |
| } |
| |
| /** |
| * Evicts all blocks for a specific HFile. |
| * <p> |
| * This is used for evict-on-close to remove all blocks of a specific HFile. |
| * |
| * @return the number of blocks evicted |
| */ |
| @Override |
| public int evictBlocksByHfileName(String hfileName) { |
| Set<BlockCacheKey> keySet = blocksByHFile.subSet( |
| new BlockCacheKey(hfileName, Long.MIN_VALUE), true, |
| new BlockCacheKey(hfileName, Long.MAX_VALUE), true); |
| |
| int numEvicted = 0; |
| for (BlockCacheKey key : keySet) { |
| if (evictBlock(key)) { |
| ++numEvicted; |
| } |
| } |
| |
| return numEvicted; |
| } |
| |
| /** |
| * Used to group bucket entries into priority buckets. There will be a |
| * BucketEntryGroup for each priority (single, multi, memory). Once bucketed, |
| * the eviction algorithm takes the appropriate number of elements out of each |
| * according to configuration parameters and their relative sizes. |
| */ |
| private class BucketEntryGroup { |
| |
| private CachedEntryQueue queue; |
| private long totalSize = 0; |
| private long bucketSize; |
| |
| public BucketEntryGroup(long bytesToFree, long blockSize, long bucketSize) { |
| this.bucketSize = bucketSize; |
| queue = new CachedEntryQueue(bytesToFree, blockSize); |
| totalSize = 0; |
| } |
| |
| public void add(Map.Entry<BlockCacheKey, BucketEntry> block) { |
| totalSize += block.getValue().getLength(); |
| queue.add(block); |
| } |
| |
| public long free(long toFree) { |
| Map.Entry<BlockCacheKey, BucketEntry> entry; |
| long freedBytes = 0; |
| // TODO avoid a cycling siutation. We find no block which is not in use and so no way to free |
| // What to do then? Caching attempt fail? Need some changes in cacheBlock API? |
| while ((entry = queue.pollLast()) != null) { |
| BucketEntry be = entry.getValue(); |
| if (be.withWriteLock(offsetLock, be::markStaleAsEvicted)) { |
| freedBytes += be.getLength(); |
| } |
| if (freedBytes >= toFree) { |
| return freedBytes; |
| } |
| } |
| return freedBytes; |
| } |
| |
| public long overflow() { |
| return totalSize - bucketSize; |
| } |
| |
| public long totalSize() { |
| return totalSize; |
| } |
| } |
| |
| /** |
| * Block Entry stored in the memory with key,data and so on |
| */ |
| static class RAMQueueEntry { |
| private final BlockCacheKey key; |
| private final Cacheable data; |
| private long accessCounter; |
| private boolean inMemory; |
| private final Recycler recycler; |
| |
| RAMQueueEntry(BlockCacheKey bck, Cacheable data, long accessCounter, boolean inMemory, |
| Recycler recycler) { |
| this.key = bck; |
| this.data = data; |
| this.accessCounter = accessCounter; |
| this.inMemory = inMemory; |
| this.recycler = recycler; |
| } |
| |
| public Cacheable getData() { |
| return data; |
| } |
| |
| public BlockCacheKey getKey() { |
| return key; |
| } |
| |
| public void access(long accessCounter) { |
| this.accessCounter = accessCounter; |
| } |
| |
| private ByteBuffAllocator getByteBuffAllocator() { |
| if (data instanceof HFileBlock) { |
| return ((HFileBlock) data).getByteBuffAllocator(); |
| } |
| return ByteBuffAllocator.HEAP; |
| } |
| |
| public BucketEntry writeToCache(final IOEngine ioEngine, final BucketAllocator alloc, |
| final LongAdder realCacheSize) throws IOException { |
| int len = data.getSerializedLength(); |
| // This cacheable thing can't be serialized |
| if (len == 0) { |
| return null; |
| } |
| long offset = alloc.allocateBlock(len); |
| boolean succ = false; |
| BucketEntry bucketEntry = null; |
| try { |
| bucketEntry = new BucketEntry(offset, len, accessCounter, inMemory, RefCnt.create(recycler), |
| getByteBuffAllocator()); |
| bucketEntry.setDeserializerReference(data.getDeserializer()); |
| if (data instanceof HFileBlock) { |
| // If an instance of HFileBlock, save on some allocations. |
| HFileBlock block = (HFileBlock) data; |
| ByteBuff sliceBuf = block.getBufferReadOnly(); |
| ByteBuffer metadata = block.getMetaData(); |
| ioEngine.write(sliceBuf, offset); |
| ioEngine.write(metadata, offset + len - metadata.limit()); |
| } else { |
| // Only used for testing. |
| ByteBuffer bb = ByteBuffer.allocate(len); |
| data.serialize(bb, true); |
| ioEngine.write(bb, offset); |
| } |
| succ = true; |
| } finally { |
| if (!succ) { |
| alloc.freeBlock(offset); |
| } |
| } |
| realCacheSize.add(len); |
| return bucketEntry; |
| } |
| } |
| |
| /** |
| * Only used in test |
| * @throws InterruptedException |
| */ |
| void stopWriterThreads() throws InterruptedException { |
| for (WriterThread writerThread : writerThreads) { |
| writerThread.disableWriter(); |
| writerThread.interrupt(); |
| writerThread.join(); |
| } |
| } |
| |
| @Override |
| public Iterator<CachedBlock> iterator() { |
| // Don't bother with ramcache since stuff is in here only a little while. |
| final Iterator<Map.Entry<BlockCacheKey, BucketEntry>> i = |
| this.backingMap.entrySet().iterator(); |
| return new Iterator<CachedBlock>() { |
| private final long now = System.nanoTime(); |
| |
| @Override |
| public boolean hasNext() { |
| return i.hasNext(); |
| } |
| |
| @Override |
| public CachedBlock next() { |
| final Map.Entry<BlockCacheKey, BucketEntry> e = i.next(); |
| return new CachedBlock() { |
| @Override |
| public String toString() { |
| return BlockCacheUtil.toString(this, now); |
| } |
| |
| @Override |
| public BlockPriority getBlockPriority() { |
| return e.getValue().getPriority(); |
| } |
| |
| @Override |
| public BlockType getBlockType() { |
| // Not held by BucketEntry. Could add it if wanted on BucketEntry creation. |
| return null; |
| } |
| |
| @Override |
| public long getOffset() { |
| return e.getKey().getOffset(); |
| } |
| |
| @Override |
| public long getSize() { |
| return e.getValue().getLength(); |
| } |
| |
| @Override |
| public long getCachedTime() { |
| return e.getValue().getCachedTime(); |
| } |
| |
| @Override |
| public String getFilename() { |
| return e.getKey().getHfileName(); |
| } |
| |
| @Override |
| public int compareTo(CachedBlock other) { |
| int diff = this.getFilename().compareTo(other.getFilename()); |
| if (diff != 0) return diff; |
| |
| diff = Long.compare(this.getOffset(), other.getOffset()); |
| if (diff != 0) return diff; |
| if (other.getCachedTime() < 0 || this.getCachedTime() < 0) { |
| throw new IllegalStateException("" + this.getCachedTime() + ", " + |
| other.getCachedTime()); |
| } |
| return Long.compare(other.getCachedTime(), this.getCachedTime()); |
| } |
| |
| @Override |
| public int hashCode() { |
| return e.getKey().hashCode(); |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (obj instanceof CachedBlock) { |
| CachedBlock cb = (CachedBlock)obj; |
| return compareTo(cb) == 0; |
| } else { |
| return false; |
| } |
| } |
| }; |
| } |
| |
| @Override |
| public void remove() { |
| throw new UnsupportedOperationException(); |
| } |
| }; |
| } |
| |
| @Override |
| public BlockCache[] getBlockCaches() { |
| return null; |
| } |
| |
| public int getRpcRefCount(BlockCacheKey cacheKey) { |
| BucketEntry bucketEntry = backingMap.get(cacheKey); |
| if (bucketEntry != null) { |
| return bucketEntry.refCnt() - (bucketEntry.markedAsEvicted.get() ? 0 : 1); |
| } |
| return 0; |
| } |
| |
| float getAcceptableFactor() { |
| return acceptableFactor; |
| } |
| |
| float getMinFactor() { |
| return minFactor; |
| } |
| |
| float getExtraFreeFactor() { |
| return extraFreeFactor; |
| } |
| |
| float getSingleFactor() { |
| return singleFactor; |
| } |
| |
| float getMultiFactor() { |
| return multiFactor; |
| } |
| |
| float getMemoryFactor() { |
| return memoryFactor; |
| } |
| |
| /** |
| * Wrapped the delegate ConcurrentMap with maintaining its block's reference count. |
| */ |
| static class RAMCache { |
| /** |
| * Defined the map as {@link ConcurrentHashMap} explicitly here, because in |
| * {@link RAMCache#get(BlockCacheKey)} and |
| * {@link RAMCache#putIfAbsent(BlockCacheKey, BucketCache.RAMQueueEntry)} , we need to |
| * guarantee the atomicity of map#computeIfPresent(key, func) and map#putIfAbsent(key, func). |
| * Besides, the func method can execute exactly once only when the key is present(or absent) |
| * and under the lock context. Otherwise, the reference count of block will be messed up. |
| * Notice that the {@link java.util.concurrent.ConcurrentSkipListMap} can not guarantee that. |
| */ |
| final ConcurrentHashMap<BlockCacheKey, RAMQueueEntry> delegate = new ConcurrentHashMap<>(); |
| |
| public boolean containsKey(BlockCacheKey key) { |
| return delegate.containsKey(key); |
| } |
| |
| public RAMQueueEntry get(BlockCacheKey key) { |
| return delegate.computeIfPresent(key, (k, re) -> { |
| // It'll be referenced by RPC, so retain atomically here. if the get and retain is not |
| // atomic, another thread may remove and release the block, when retaining in this thread we |
| // may retain a block with refCnt=0 which is disallowed. (see HBASE-22422) |
| re.getData().retain(); |
| return re; |
| }); |
| } |
| |
| /** |
| * Return the previous associated value, or null if absent. It has the same meaning as |
| * {@link ConcurrentMap#putIfAbsent(Object, Object)} |
| */ |
| public RAMQueueEntry putIfAbsent(BlockCacheKey key, RAMQueueEntry entry) { |
| AtomicBoolean absent = new AtomicBoolean(false); |
| RAMQueueEntry re = delegate.computeIfAbsent(key, k -> { |
| // The RAMCache reference to this entry, so reference count should be increment. |
| entry.getData().retain(); |
| absent.set(true); |
| return entry; |
| }); |
| return absent.get() ? null : re; |
| } |
| |
| public boolean remove(BlockCacheKey key) { |
| return remove(key, re->{}); |
| } |
| |
| /** |
| * Defined an {@link Consumer} here, because once the removed entry release its reference count, |
| * then it's ByteBuffers may be recycled and accessing it outside this method will be thrown an |
| * exception. the consumer will access entry to remove before release its reference count. |
| * Notice, don't change its reference count in the {@link Consumer} |
| */ |
| public boolean remove(BlockCacheKey key, Consumer<RAMQueueEntry> action) { |
| RAMQueueEntry previous = delegate.remove(key); |
| action.accept(previous); |
| if (previous != null) { |
| previous.getData().release(); |
| } |
| return previous != null; |
| } |
| |
| public boolean isEmpty() { |
| return delegate.isEmpty(); |
| } |
| |
| public void clear() { |
| Iterator<Map.Entry<BlockCacheKey, RAMQueueEntry>> it = delegate.entrySet().iterator(); |
| while (it.hasNext()) { |
| RAMQueueEntry re = it.next().getValue(); |
| it.remove(); |
| re.getData().release(); |
| } |
| } |
| } |
| } |
