Author: stack
Date: Wed Jul 27 17:50:36 2011
New Revision: 1151559
URL: http://svn.apache.org/viewvc?rev=1151559&view=rev
Log:
HBASE-1938 Make in-memory table scanning faster
Modified:
hbase/trunk/CHANGES.txt
hbase/trunk/src/main/java/org/apache/hadoop/hbase/regionserver/KeyValueSkipListSet.java
hbase/trunk/src/main/java/org/apache/hadoop/hbase/regionserver/MemStore.java
Modified: hbase/trunk/CHANGES.txt
URL:
http://svn.apache.org/viewvc/hbase/trunk/CHANGES.txt?rev=1151559&r1=1151558&r2=1151559&view=diff
==============================================================================
--- hbase/trunk/CHANGES.txt (original)
+++ hbase/trunk/CHANGES.txt Wed Jul 27 17:50:36 2011
@@ -339,6 +339,7 @@ Release 0.91.0 - Unreleased
HBASE-4142 Advise against large batches in javadoc for
HTable#put(List<Put>)
HBASE-4139 [stargate] Update ScannerModel with support for filter package
additions
+ HBASE-1938 Make in-memory table scanning faster (nkeywal)
TASKS
HBASE-3559 Move report of split to master OFF the heartbeat channel
Modified:
hbase/trunk/src/main/java/org/apache/hadoop/hbase/regionserver/KeyValueSkipListSet.java
URL:
http://svn.apache.org/viewvc/hbase/trunk/src/main/java/org/apache/hadoop/hbase/regionserver/KeyValueSkipListSet.java?rev=1151559&r1=1151558&r2=1151559&view=diff
==============================================================================
---
hbase/trunk/src/main/java/org/apache/hadoop/hbase/regionserver/KeyValueSkipListSet.java
(original)
+++
hbase/trunk/src/main/java/org/apache/hadoop/hbase/regionserver/KeyValueSkipListSet.java
Wed Jul 27 17:50:36 2011
@@ -24,7 +24,6 @@ import org.apache.hadoop.hbase.KeyValue;
import java.util.Collection;
import java.util.Comparator;
import java.util.Iterator;
-import java.util.Map;
import java.util.NavigableSet;
import java.util.SortedSet;
import java.util.concurrent.ConcurrentNavigableMap;
@@ -55,37 +54,12 @@ class KeyValueSkipListSet implements Nav
this.delegatee = m;
}
- /**
- * Iterator that maps Iterator calls to return the value component of the
- * passed-in Map.Entry Iterator.
- */
- static class MapEntryIterator implements Iterator<KeyValue> {
- private final Iterator<Map.Entry<KeyValue, KeyValue>> iterator;
-
- MapEntryIterator(final Iterator<Map.Entry<KeyValue, KeyValue>> i) {
- this.iterator = i;
- }
-
- public boolean hasNext() {
- return this.iterator.hasNext();
- }
-
- public KeyValue next() {
- return this.iterator.next().getValue();
- }
-
- public void remove() {
- this.iterator.remove();
- }
- }
-
public KeyValue ceiling(KeyValue e) {
throw new UnsupportedOperationException("Not implemented");
}
public Iterator<KeyValue> descendingIterator() {
- return new MapEntryIterator(this.delegatee.descendingMap().entrySet().
- iterator());
+ return this.delegatee.descendingMap().values().iterator();
}
public NavigableSet<KeyValue> descendingSet() {
@@ -110,7 +84,7 @@ class KeyValueSkipListSet implements Nav
}
public Iterator<KeyValue> iterator() {
- return new MapEntryIterator(this.delegatee.entrySet().iterator());
+ return this.delegatee.values().iterator();
}
public KeyValue lower(KeyValue e) {
Modified:
hbase/trunk/src/main/java/org/apache/hadoop/hbase/regionserver/MemStore.java
URL:
http://svn.apache.org/viewvc/hbase/trunk/src/main/java/org/apache/hadoop/hbase/regionserver/MemStore.java?rev=1151559&r1=1151558&r2=1151559&view=diff
==============================================================================
---
hbase/trunk/src/main/java/org/apache/hadoop/hbase/regionserver/MemStore.java
(original)
+++
hbase/trunk/src/main/java/org/apache/hadoop/hbase/regionserver/MemStore.java
Wed Jul 27 17:50:36 2011
@@ -646,11 +646,15 @@ public class MemStore implements HeapSiz
private KeyValue snapshotNextRow = null;
// iterator based scanning.
- Iterator<KeyValue> kvsetIt;
- Iterator<KeyValue> snapshotIt;
+ private Iterator<KeyValue> kvsetIt;
+ private Iterator<KeyValue> snapshotIt;
// number of iterations in this reseek operation
- int numIterReseek;
+ private int numIterReseek;
+
+
+ // the pre-calculated KeyValue to be returned by peek() or next()
+ private KeyValue theNext;
/*
Some notes...
@@ -676,9 +680,9 @@ public class MemStore implements HeapSiz
//DebugPrint.println(" MS new@" + hashCode());
}
- protected KeyValue getNext(Iterator<KeyValue> it) {
+ protected KeyValue getNext(Iterator<KeyValue> it, long readPoint) {
KeyValue ret = null;
- long readPoint = ReadWriteConsistencyControl.getThreadReadPoint();
+ //long readPoint = ReadWriteConsistencyControl.getThreadReadPoint();
//DebugPrint.println( " MS@" + hashCode() + ": threadpoint = " +
readPoint);
while (ret == null && it.hasNext()) {
@@ -710,9 +714,11 @@ public class MemStore implements HeapSiz
kvsetIt = kvTail.iterator();
snapshotIt = snapshotTail.iterator();
- kvsetNextRow = getNext(kvsetIt);
- snapshotNextRow = getNext(snapshotIt);
+ long readPoint = ReadWriteConsistencyControl.getThreadReadPoint();
+ kvsetNextRow = getNext(kvsetIt, readPoint);
+ snapshotNextRow = getNext(snapshotIt, readPoint);
+ theNext = getLowest();
//long readPoint = ReadWriteConsistencyControl.getThreadReadPoint();
//DebugPrint.println( " MS@" + hashCode() + " kvset seek: " +
kvsetNextRow + " with size = " +
@@ -720,19 +726,18 @@ public class MemStore implements HeapSiz
//DebugPrint.println( " MS@" + hashCode() + " snapshot seek: " +
snapshotNextRow + " with size = " +
// snapshot.size() + " threadread = " + readPoint);
-
- KeyValue lowest = getLowest();
-
- // has data := (lowest != null)
- return lowest != null;
+ // has data
+ return (theNext != null);
}
@Override
- public boolean reseek(KeyValue key) {
+ public synchronized boolean reseek(KeyValue key) {
+
numIterReseek = reseekNumKeys;
while (kvsetNextRow != null &&
comparator.compare(kvsetNextRow, key) < 0) {
- kvsetNextRow = getNext(kvsetIt);
+ kvsetNextRow = getNext(kvsetIt,
+ ReadWriteConsistencyControl.getThreadReadPoint());
// if we scanned enough entries but still not able to find the
// kv we are looking for, better cut our costs and do a tree
// scan using seek.
@@ -743,7 +748,8 @@ public class MemStore implements HeapSiz
while (snapshotNextRow != null &&
comparator.compare(snapshotNextRow, key) < 0) {
- snapshotNextRow = getNext(snapshotIt);
+ snapshotNextRow = getNext(snapshotIt,
+ ReadWriteConsistencyControl.getThreadReadPoint());
// if we scanned enough entries but still not able to find the
// kv we are looking for, better cut our costs and do a tree
// scan using seek.
@@ -751,38 +757,48 @@ public class MemStore implements HeapSiz
return seek(key);
}
}
- return (kvsetNextRow != null || snapshotNextRow != null);
+
+ // Calculate the next value
+ theNext = getLowest();
+
+ return (theNext != null);
}
+ @Override
public synchronized KeyValue peek() {
//DebugPrint.println(" MS@" + hashCode() + " peek = " + getLowest());
- return getLowest();
+ return theNext;
}
+ @Override
public synchronized KeyValue next() {
- KeyValue theNext = getLowest();
if (theNext == null) {
return null;
}
+ KeyValue ret = theNext;
+
// Advance one of the iterators
+ long readPoint = ReadWriteConsistencyControl.getThreadReadPoint();
if (theNext == kvsetNextRow) {
- kvsetNextRow = getNext(kvsetIt);
+ kvsetNextRow = getNext(kvsetIt, readPoint);
} else {
- snapshotNextRow = getNext(snapshotIt);
+ snapshotNextRow = getNext(snapshotIt, readPoint);
}
- //long readpoint = ReadWriteConsistencyControl.getThreadReadPoint();
- //DebugPrint.println(" MS@" + hashCode() + " next: " + theNext + "
next_next: " +
- // getLowest() + " threadpoint=" + readpoint);
- return theNext;
+ // Calculate the next value
+ theNext = getLowest();
+
+ //readpoint = ReadWriteConsistencyControl.getThreadReadPoint();
+ //DebugPrint.println(" MS@" + hashCode() + " next: " + theNext +
+ // " next_next: " + getLowest() + " threadpoint=" + readpoint);
+ return ret;
}
protected KeyValue getLowest() {
- return getLower(kvsetNextRow,
- snapshotNextRow);
+ return getLower(kvsetNextRow, snapshotNextRow);
}
/*
@@ -791,14 +807,15 @@ public class MemStore implements HeapSiz
* comparator.
*/
protected KeyValue getLower(KeyValue first, KeyValue second) {
- if (first == null && second == null) {
- return null;
+ if (first == null) {
+ return second;
}
- if (first != null && second != null) {
- int compare = comparator.compare(first, second);
- return (compare <= 0 ? first : second);
+ if (second == null) {
+ return first;
}
- return (first != null ? first : second);
+
+ int compare = comparator.compare(first, second);
+ return (compare <= 0 ? first : second);
}
public synchronized void close() {
