Author: jbellis
Date: Mon May 3 20:46:44 2010
New Revision: 940612
URL: http://svn.apache.org/viewvc?rev=940612&view=rev
Log:
Optimize TimeUUID comparisons by computing timestamp from raw bytes rather than
creating temporary UUID objects. patch by James Golick; reviewed by Sylvain
Lebrense and jbellis for CASSANDRA-1043
Added:
cassandra/trunk/test/unit/org/apache/cassandra/db/marshal/TimeUUIDTypeTest.java
Modified:
cassandra/trunk/src/java/org/apache/cassandra/db/marshal/TimeUUIDType.java
Modified:
cassandra/trunk/src/java/org/apache/cassandra/db/marshal/TimeUUIDType.java
URL:
http://svn.apache.org/viewvc/cassandra/trunk/src/java/org/apache/cassandra/db/marshal/TimeUUIDType.java?rev=940612&r1=940611&r2=940612&view=diff
==============================================================================
--- cassandra/trunk/src/java/org/apache/cassandra/db/marshal/TimeUUIDType.java
(original)
+++ cassandra/trunk/src/java/org/apache/cassandra/db/marshal/TimeUUIDType.java
Mon May 3 20:46:44 2010
@@ -37,11 +37,27 @@ public class TimeUUIDType extends Abstra
return 1;
}
- long t1 = LexicalUUIDType.getUUID(o1).timestamp();
- long t2 = LexicalUUIDType.getUUID(o2).timestamp();
+ long t1 = getTimestamp(o1);
+ long t2 = getTimestamp(o2);
return t1 < t2 ? -1 : (t1 > t2 ? 1 : FBUtilities.compareByteArrays(o1,
o2));
}
+ static long getTimestamp(byte[] bytes)
+ {
+ long low = 0;
+ int mid = 0;
+ int hi = 0;
+
+ for (int i = 0; i < 4; i++)
+ low = (low << 8) | (bytes[i] & 0xff);
+ for (int i = 4; i < 6; i++)
+ mid = (mid << 8) | (bytes[i] & 0xff);
+ for (int i = 6; i < 8; i++)
+ hi = (hi << 8) | (bytes[i] & 0xff);
+
+ return low + ((long)mid << 32) + ((long)(hi & 0x0FFF) << 48);
+ }
+
public String getString(byte[] bytes)
{
if (bytes.length == 0)
Added:
cassandra/trunk/test/unit/org/apache/cassandra/db/marshal/TimeUUIDTypeTest.java
URL:
http://svn.apache.org/viewvc/cassandra/trunk/test/unit/org/apache/cassandra/db/marshal/TimeUUIDTypeTest.java?rev=940612&view=auto
==============================================================================
---
cassandra/trunk/test/unit/org/apache/cassandra/db/marshal/TimeUUIDTypeTest.java
(added)
+++
cassandra/trunk/test/unit/org/apache/cassandra/db/marshal/TimeUUIDTypeTest.java
Mon May 3 20:46:44 2010
@@ -0,0 +1,77 @@
+/*
+* 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.cassandra.db.marshal;
+
+import org.junit.Test;
+import static org.junit.Assert.assertEquals;
+
+import org.apache.cassandra.CleanupHelper;
+import org.apache.cassandra.db.marshal.TimeUUIDType;
+
+import org.safehaus.uuid.UUID;
+import org.safehaus.uuid.UUIDGenerator;
+
+public class TimeUUIDTypeTest extends CleanupHelper
+{
+ TimeUUIDType timeUUIDType = new TimeUUIDType();
+ UUIDGenerator generator = UUIDGenerator.getInstance();
+
+ @Test
+ public void testEquality()
+ {
+ UUID a = generator.generateTimeBasedUUID();
+ UUID b = new UUID(a.asByteArray());
+
+ assertEquals(0, timeUUIDType.compare(a.asByteArray(),
b.asByteArray()));
+ }
+
+ @Test
+ public void testSmaller()
+ {
+ UUID a = generator.generateTimeBasedUUID();
+ UUID b = generator.generateTimeBasedUUID();
+ UUID c = generator.generateTimeBasedUUID();
+
+ assertEquals(-1, timeUUIDType.compare(a.asByteArray(),
b.asByteArray()));
+ assertEquals(-1, timeUUIDType.compare(b.asByteArray(),
c.asByteArray()));
+ assertEquals(-1, timeUUIDType.compare(a.asByteArray(),
c.asByteArray()));
+ }
+
+ @Test
+ public void testBigger()
+ {
+ UUID a = generator.generateTimeBasedUUID();
+ UUID b = generator.generateTimeBasedUUID();
+ UUID c = generator.generateTimeBasedUUID();
+
+ assertEquals(1, timeUUIDType.compare(c.asByteArray(),
b.asByteArray()));
+ assertEquals(1, timeUUIDType.compare(b.asByteArray(),
a.asByteArray()));
+ assertEquals(1, timeUUIDType.compare(c.asByteArray(),
a.asByteArray()));
+ }
+
+ @Test
+ public void testTimestamp()
+ {
+ for (int i = 0; i < 100; i++)
+ {
+ UUID uuid = generator.generateTimeBasedUUID();
+ assert TimeUUIDType.getTimestamp(uuid.asByteArray()) ==
LexicalUUIDType.getUUID(uuid.asByteArray()).timestamp();
+ }
+ }
+}
