Author: jbellis
Date: Fri Jun 4 22:13:21 2010
New Revision: 951594
URL: http://svn.apache.org/viewvc?rev=951594&view=rev
Log:
optimize away copy of sliced row on memtable read path. patch by mdennis;
reviewed by jbellis for CASSANDRA-1046
Modified:
cassandra/trunk/CHANGES.txt
cassandra/trunk/src/java/org/apache/cassandra/db/ColumnFamily.java
cassandra/trunk/src/java/org/apache/cassandra/db/Memtable.java
Modified: cassandra/trunk/CHANGES.txt
URL:
http://svn.apache.org/viewvc/cassandra/trunk/CHANGES.txt?rev=951594&r1=951593&r2=951594&view=diff
==============================================================================
--- cassandra/trunk/CHANGES.txt (original)
+++ cassandra/trunk/CHANGES.txt Fri Jun 4 22:13:21 2010
@@ -23,6 +23,7 @@ dev
* removed deprecated batch_insert and get_range_slice methods (CASSANDRA-1065)
* add truncate thrift method (CASSANDRA-531)
* http mini-interface using mx4j (CASSANDRA-1068)
+ * optimize away copy of sliced row on memtable read path (CASSANDRA-1046)
0.6.3
Modified: cassandra/trunk/src/java/org/apache/cassandra/db/ColumnFamily.java
URL:
http://svn.apache.org/viewvc/cassandra/trunk/src/java/org/apache/cassandra/db/ColumnFamily.java?rev=951594&r1=951593&r2=951594&view=diff
==============================================================================
--- cassandra/trunk/src/java/org/apache/cassandra/db/ColumnFamily.java
(original)
+++ cassandra/trunk/src/java/org/apache/cassandra/db/ColumnFamily.java Fri Jun
4 22:13:21 2010
@@ -18,10 +18,7 @@
package org.apache.cassandra.db;
-import java.util.Collection;
-import java.util.Map;
-import java.util.Set;
-import java.util.SortedSet;
+import java.util.*;
import java.util.concurrent.ConcurrentSkipListMap;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
@@ -265,6 +262,11 @@ public class ColumnFamily implements ICo
return columns.values();
}
+ public Collection<IColumn> getReverseSortedColumns()
+ {
+ return columns.descendingMap().values();
+ }
+
public Map<byte[], IColumn> getColumnsMap()
{
return columns;
Modified: cassandra/trunk/src/java/org/apache/cassandra/db/Memtable.java
URL:
http://svn.apache.org/viewvc/cassandra/trunk/src/java/org/apache/cassandra/db/Memtable.java?rev=951594&r1=951593&r2=951594&view=diff
==============================================================================
--- cassandra/trunk/src/java/org/apache/cassandra/db/Memtable.java (original)
+++ cassandra/trunk/src/java/org/apache/cassandra/db/Memtable.java Fri Jun 4
22:13:21 2010
@@ -26,9 +26,10 @@ import java.util.concurrent.ExecutorServ
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.locks.Condition;
+import com.google.common.collect.Iterators;
+import com.google.common.collect.PeekingIterator;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
-import org.apache.commons.lang.ArrayUtils;
import org.apache.cassandra.config.DatabaseDescriptor;
import org.apache.cassandra.db.filter.*;
@@ -207,39 +208,24 @@ public class Memtable implements Compara
public static IColumnIterator getSliceIterator(final DecoratedKey key,
final ColumnFamily cf, SliceQueryFilter filter, AbstractType typeComparator)
{
assert cf != null;
- Collection<IColumn> rawColumns = cf.getSortedColumns();
- Collection<IColumn> filteredColumns =
filter.applyPredicate(rawColumns);
+ final boolean isSuper = cf.isSuper();
+ final Collection<IColumn> filteredColumns = filter.reversed ?
filter.applyPredicate(cf.getReverseSortedColumns()) :
filter.applyPredicate(cf.getSortedColumns());
- final IColumn columns[] = filteredColumns.toArray(new IColumn[0]);
- // TODO if we are dealing with supercolumns, we need to clone them
while we have the read lock since they can be modified later
- if (filter.reversed)
- ArrayUtils.reverse(columns);
- IColumn startIColumn;
- final boolean isStandard = !cf.isSuper();
- if (isStandard)
- startIColumn = new Column(filter.start);
- else
- startIColumn = new SuperColumn(filter.start, null,
cf.getClockType(), cf.getReconciler()); // ok to not have subcolumnComparator
since we won't be adding columns to this object
-
- // can't use a ColumnComparatorFactory comparator since those compare
on both name and time (and thus will fail to match
- // our dummy column, since the time there is arbitrary).
+ // ok to not have subcolumnComparator since we won't be adding columns
to this object
+ IColumn startColumn = isSuper ? new SuperColumn(filter.start, null,
cf.getClockType(), cf.getReconciler()) : new Column(filter.start);
Comparator<IColumn> comparator =
filter.getColumnComparator(typeComparator);
- int index;
- if (filter.start.length == 0 && filter.reversed)
- {
- /* scan from the largest column in descending order */
- index = 0;
- }
- else
+
+ final PeekingIterator<IColumn> filteredIter =
Iterators.peekingIterator(filteredColumns.iterator());
+ if (!filter.reversed || filter.start.length != 0)
{
- index = Arrays.binarySearch(columns, startIColumn, comparator);
+ while (filteredIter.hasNext() &&
comparator.compare(filteredIter.peek(), startColumn) < 0)
+ {
+ filteredIter.next();
+ }
}
- final int startIndex = index < 0 ? -(index + 1) : index;
return new AbstractColumnIterator()
{
- private int curIndex_ = startIndex;
-
public ColumnFamily getColumnFamily()
{
return cf;
@@ -252,13 +238,14 @@ public class Memtable implements Compara
public boolean hasNext()
{
- return curIndex_ < columns.length;
+ return filteredIter.hasNext();
}
public IColumn next()
{
// clone supercolumns so caller can freely removeDeleted or
otherwise mutate it
- return isStandard ? columns[curIndex_++] :
((SuperColumn)columns[curIndex_++]).cloneMe();
+ // TODO can't the callers that wish to mutate it clone it
themselves?
+ return isSuper ? ((SuperColumn) filteredIter.next()).cloneMe()
: filteredIter.next();
}
};
}
