Apache
/
hbase
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

HBASE-4752 Don't create an unnecessary LinkedList when evicting from the BlockCache 

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1201516 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Zhihong Yu 2011-11-13 21:17:35 +00:00
parent 87c500ccf3
commit 7d23c9afb1
3 changed files with 24 additions and 37 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
src/main/java/org/apache/hadoop/hbase/io/hfile/CachedBlockQueue.java
View File

@ -19,8 +19,7 @@
*/
package org.apache.hadoop.hbase.io.hfile;
import java.util.LinkedList;
import java.util.PriorityQueue;
import com.google.common.collect.MinMaxPriorityQueue;
import org.apache.hadoop.hbase.io.HeapSize;
@ -39,7 +38,7 @@ import org.apache.hadoop.hbase.io.HeapSize;
*/
public class CachedBlockQueue implements HeapSize {
private PriorityQueue<CachedBlock> queue;
private MinMaxPriorityQueue<CachedBlock> queue;
private long heapSize;
private long maxSize;
@ -51,7 +50,7 @@ public class CachedBlockQueue implements HeapSize {
public CachedBlockQueue(long maxSize, long blockSize) {
int initialSize = (int)(maxSize / blockSize);
if(initialSize == 0) initialSize++;
queue = new PriorityQueue<CachedBlock>(initialSize);
queue = MinMaxPriorityQueue.expectedSize(initialSize).create();
heapSize = 0;
this.maxSize = maxSize;
}
@ -84,14 +83,19 @@ public class CachedBlockQueue implements HeapSize {
}
/**
* @return a sorted List of all elements in this queue, in descending order
* @return The next element in this queue, or {@code null} if the queue is
* empty.
*/
public LinkedList<CachedBlock> get() {
LinkedList<CachedBlock> blocks = new LinkedList<CachedBlock>();
while (!queue.isEmpty()) {
blocks.addFirst(queue.poll());
}
return blocks;
public CachedBlock poll() {
return queue.poll();
}
/**
* @return The last element in this queue, or {@code null} if the queue is
* empty.
*/
public CachedBlock pollLast() {
return queue.pollLast();
}
/**

7
src/main/java/org/apache/hadoop/hbase/io/hfile/LruBlockCache.java
View File

@ -24,7 +24,6 @@ import java.lang.ref.WeakReference;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.PriorityQueue;
@ -494,11 +493,11 @@ public class LruBlockCache implements BlockCache, HeapSize {
}
public long free(long toFree) {
LinkedList<CachedBlock> blocks = queue.get();
CachedBlock cb;
long freedBytes = 0;
for(CachedBlock cb: blocks) {
while ((cb = queue.pollLast()) != null) {
freedBytes += evictBlock(cb);
if(freedBytes >= toFree) {
if (freedBytes >= toFree) {
return freedBytes;
}
}

28
src/test/java/org/apache/hadoop/hbase/io/hfile/TestCachedBlockQueue.java
View File

@ -63,17 +63,9 @@ public class TestCachedBlockQueue extends TestCase {
assertEquals(queue.heapSize(), expectedSize);
LinkedList<org.apache.hadoop.hbase.io.hfile.CachedBlock> blocks =
queue.get();
assertEquals(blocks.poll().getName(), "cb1");
assertEquals(blocks.poll().getName(), "cb2");
assertEquals(blocks.poll().getName(), "cb3");
assertEquals(blocks.poll().getName(), "cb4");
assertEquals(blocks.poll().getName(), "cb5");
assertEquals(blocks.poll().getName(), "cb6");
assertEquals(blocks.poll().getName(), "cb7");
assertEquals(blocks.poll().getName(), "cb8");
for (int i = 1; i <= 8; i++) {
assertEquals(queue.pollLast().getName(), "cb"+i);
}
}
public void testQueueSmallBlockEdgeCase() throws Exception {
@ -116,17 +108,9 @@ public class TestCachedBlockQueue extends TestCase {
assertEquals(queue.heapSize(), expectedSize);
LinkedList<org.apache.hadoop.hbase.io.hfile.CachedBlock> blocks = queue.get();
assertEquals(blocks.poll().getName(), "cb0");
assertEquals(blocks.poll().getName(), "cb1");
assertEquals(blocks.poll().getName(), "cb2");
assertEquals(blocks.poll().getName(), "cb3");
assertEquals(blocks.poll().getName(), "cb4");
assertEquals(blocks.poll().getName(), "cb5");
assertEquals(blocks.poll().getName(), "cb6");
assertEquals(blocks.poll().getName(), "cb7");
assertEquals(blocks.poll().getName(), "cb8");
for (int i = 0; i <= 8; i++) {
assertEquals(queue.pollLast().getName(), "cb"+i);
}
}
private static class CachedBlock extends org.apache.hadoop.hbase.io.hfile.CachedBlock