CombinedBlockCache (Apache HBase

java.lang.Object
- org.apache.hadoop.hbase.io.hfile.CombinedBlockCache

所有已实现的接口:

Iterable<CachedBlock>, HeapSize, BlockCache, ResizableBlockCache

直接已知子类:

InclusiveCombinedBlockCache
```
@InterfaceAudience.Private
public class CombinedBlockCache
extends Object
implements ResizableBlockCache, HeapSize
```
CombinedBlockCache is an abstraction layer that combines LruBlockCache and BucketCache. The smaller lruCache is used to cache bloom blocks and index blocks. The larger l2Cache is used to cache data blocks. getBlock(BlockCacheKey, boolean, boolean, boolean) reads first from the smaller lruCache before looking for the block in the l2Cache. Blocks evicted from lruCache are put into the bucket cache. Metrics are the combined size and hits and misses of both caches.

嵌套类概要

嵌套类
限定符和类型类和说明

static class CombinedBlockCache.CombinedCacheStats

嵌套类
限定符和类型	类和说明
`static class`	`CombinedBlockCache.CombinedCacheStats`

字段概要

字段
限定符和类型字段和说明

protected CombinedBlockCache.CombinedCacheStats combinedCacheStats

protected BlockCache l2Cache

protected LruBlockCache lruCache

字段
限定符和类型	字段和说明
`protected CombinedBlockCache.CombinedCacheStats`	`combinedCacheStats`
`protected BlockCache`	`l2Cache`
`protected LruBlockCache`	`lruCache`

构造器概要

构造器
构造器和说明

CombinedBlockCache(LruBlockCache lruCache, BlockCache l2Cache)

构造器
构造器和说明
`CombinedBlockCache(LruBlockCache lruCache, BlockCache l2Cache)`

方法概要

方法
限定符和类型	方法和说明
`void`	`cacheBlock(BlockCacheKey cacheKey, Cacheable buf)` Add block to cache (defaults to not in-memory).
`void`	`cacheBlock(BlockCacheKey cacheKey, Cacheable buf, boolean inMemory, boolean cacheDataInL1)` Add block to cache.
`boolean`	`evictBlock(BlockCacheKey cacheKey)` Evict block from cache.
`int`	`evictBlocksByHfileName(String hfileName)` Evicts all blocks for the given HFile.
`Cacheable`	`getBlock(BlockCacheKey cacheKey, boolean caching, boolean repeat, boolean updateCacheMetrics)` Fetch block from cache.
`BlockCache[]`	`getBlockCaches()`
`long`	`getBlockCount()` Returns the number of blocks currently cached in the block cache.
`long`	`getCurrentDataSize()` Returns the occupied size of data blocks, in bytes.
`long`	`getCurrentSize()` Returns the occupied size of the block cache, in bytes.
`long`	`getDataBlockCount()` Returns the number of data blocks currently cached in the block cache.
`long`	`getFreeSize()` Returns the free size of the block cache, in bytes.
`long`	`getMaxSize()` Returns the Max size of the block cache, in bytes.
`CacheStats`	`getStats()` Get the statistics for this block cache.
`long`	`heapSize()`
`Iterator<CachedBlock>`	`iterator()`
`void`	`setMaxSize(long size)` Sets the max heap size that can be used by the BlockCache.
`void`	`shutdown()` Shutdown the cache.
`long`	`size()` Returns the total size of the block cache, in bytes.

从类继承的方法 java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- 字段详细资料
  - lruCache
```
protected final LruBlockCache lruCache
```
  - l2Cache
```
protected final BlockCache l2Cache
```
  - combinedCacheStats
```
protected final CombinedBlockCache.CombinedCacheStats combinedCacheStats
```
- 构造器详细资料
  - CombinedBlockCache
```
public CombinedBlockCache(LruBlockCache lruCache,
                  BlockCache l2Cache)
```
- 方法详细资料
  - heapSize
```
public long heapSize()
```
    指定者:
    
    heapSize 在接口中 HeapSize
  - cacheBlock
```
public void cacheBlock(BlockCacheKey cacheKey,
              Cacheable buf,
              boolean inMemory,
              boolean cacheDataInL1)
```
    从接口复制的说明: BlockCache
    
    Add block to cache.
    
    指定者:
    
    cacheBlock 在接口中 BlockCache
    
    参数:
    cacheKey - The block's cache key.
    buf - The block contents wrapped in a ByteBuffer.
    inMemory - Whether block should be treated as in-memory
    cacheDataInL1 - If multi-tier block cache deploy -- i.e. has an L1 and L2 tier -- then if this flag is true, cache data blocks up in the L1 tier (meta blocks are probably being cached in L1 already).
  - cacheBlock
```
public void cacheBlock(BlockCacheKey cacheKey,
              Cacheable buf)
```
    从接口复制的说明: BlockCache
    
    Add block to cache (defaults to not in-memory).
    
    指定者:
    
    cacheBlock 在接口中 BlockCache
    
    参数:
    cacheKey - The block's cache key.
    buf - The object to cache.
  - getBlock
```
public Cacheable getBlock(BlockCacheKey cacheKey,
                 boolean caching,
                 boolean repeat,
                 boolean updateCacheMetrics)
```
    从接口复制的说明: BlockCache
    
    Fetch block from cache.
    
    指定者:
    
    getBlock 在接口中 BlockCache
    
    参数:
    cacheKey - Block to fetch.
    caching - Whether this request has caching enabled (used for stats)
    repeat - Whether this is a repeat lookup for the same block (used to avoid double counting cache misses when doing double-check locking)
    updateCacheMetrics - Whether to update cache metrics or not
    
    返回:
    Block or null if block is not in 2 cache.
  - evictBlock
```
public boolean evictBlock(BlockCacheKey cacheKey)
```
    从接口复制的说明: BlockCache
    
    Evict block from cache.
    
    指定者:
    
    evictBlock 在接口中 BlockCache
    
    参数:
    cacheKey - Block to evict
    
    返回:
    true if block existed and was evicted, false if not
  - evictBlocksByHfileName
```
public int evictBlocksByHfileName(String hfileName)
```
    从接口复制的说明: BlockCache
    
    Evicts all blocks for the given HFile.
    
    指定者:
    
    evictBlocksByHfileName 在接口中 BlockCache
    
    返回:
    the number of blocks evicted
  - getStats
```
public CacheStats getStats()
```
    从接口复制的说明: BlockCache
    
    Get the statistics for this block cache.
    
    指定者:
    
    getStats 在接口中 BlockCache
    
    返回:
    Stats
  - shutdown
```
public void shutdown()
```
    从接口复制的说明: BlockCache
    
    Shutdown the cache.
    
    指定者:
    
    shutdown 在接口中 BlockCache
  - size
```
public long size()
```
    从接口复制的说明: BlockCache
    
    Returns the total size of the block cache, in bytes.
    
    指定者:
    
    size 在接口中 BlockCache
    
    返回:
    size of cache, in bytes
  - getMaxSize
```
public long getMaxSize()
```
    从接口复制的说明: BlockCache
    
    Returns the Max size of the block cache, in bytes.
    
    指定者:
    
    getMaxSize 在接口中 BlockCache
    
    返回:
    size of cache, in bytes
  - getFreeSize
```
public long getFreeSize()
```
    从接口复制的说明: BlockCache
    
    Returns the free size of the block cache, in bytes.
    
    指定者:
    
    getFreeSize 在接口中 BlockCache
    
    返回:
    free space in cache, in bytes
  - getCurrentSize
```
public long getCurrentSize()
```
    从接口复制的说明: BlockCache
    
    Returns the occupied size of the block cache, in bytes.
    
    指定者:
    
    getCurrentSize 在接口中 BlockCache
    
    返回:
    occupied space in cache, in bytes
  - getCurrentDataSize
```
public long getCurrentDataSize()
```
    从接口复制的说明: BlockCache
    
    Returns the occupied size of data blocks, in bytes.
    
    指定者:
    
    getCurrentDataSize 在接口中 BlockCache
    
    返回:
    occupied space in cache, in bytes
  - getBlockCount
```
public long getBlockCount()
```
    从接口复制的说明: BlockCache
    
    Returns the number of blocks currently cached in the block cache.
    
    指定者:
    
    getBlockCount 在接口中 BlockCache
    
    返回:
    number of blocks in the cache
  - getDataBlockCount
```
public long getDataBlockCount()
```
    从接口复制的说明: BlockCache
    
    Returns the number of data blocks currently cached in the block cache.
    
    指定者:
    
    getDataBlockCount 在接口中 BlockCache
    
    返回:
    number of blocks in the cache
  - iterator
```
public Iterator<CachedBlock> iterator()
```
    指定者:
    
    iterator 在接口中 Iterable<CachedBlock>
    
    指定者:
    
    iterator 在接口中 BlockCache
    
    返回:
    Iterator over the blocks in the cache.
  - getBlockCaches
```
public BlockCache[] getBlockCaches()
```
    指定者:
    
    getBlockCaches 在接口中 BlockCache
    
    返回:
    The list of sub blockcaches that make up this one; returns null if no sub caches.
  - setMaxSize
```
public void setMaxSize(long size)
```
    从接口复制的说明: ResizableBlockCache
    
    Sets the max heap size that can be used by the BlockCache.
    
    指定者:
    
    setMaxSize 在接口中 ResizableBlockCache
    
    参数:
    size - The max heap size.

类 CombinedBlockCache

嵌套类概要

字段概要

构造器概要

方法概要

从类继承的方法 java.lang.Object

字段详细资料

lruCache

l2Cache

combinedCacheStats

构造器详细资料

CombinedBlockCache

方法详细资料

heapSize

cacheBlock

cacheBlock

getBlock

evictBlock

evictBlocksByHfileName

getStats

shutdown

size

getMaxSize

getFreeSize

getCurrentSize

getCurrentDataSize

getBlockCount

getDataBlockCount

iterator

getBlockCaches

setMaxSize