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Posted to commits@cassandra.apache.org by ja...@apache.org on 2015/06/17 23:34:29 UTC
cassandra git commit: ArrivalWindow should use primitives
Repository: cassandra
Updated Branches:
refs/heads/cassandra-2.0 ec52e77ec -> ad8047abd
ArrivalWindow should use primitives
patch by sankalp kohli; reviewed by jasobrown for CASSANDRA-9496
Project: http://git-wip-us.apache.org/repos/asf/cassandra/repo
Commit: http://git-wip-us.apache.org/repos/asf/cassandra/commit/ad8047ab
Tree: http://git-wip-us.apache.org/repos/asf/cassandra/tree/ad8047ab
Diff: http://git-wip-us.apache.org/repos/asf/cassandra/diff/ad8047ab
Branch: refs/heads/cassandra-2.0
Commit: ad8047abdf5db6652b9586e039debb1e855db09a
Parents: ec52e77
Author: Jason Brown <ja...@gmail.com>
Authored: Wed Jun 17 14:33:44 2015 -0700
Committer: Jason Brown <ja...@gmail.com>
Committed: Wed Jun 17 14:33:44 2015 -0700
----------------------------------------------------------------------
CHANGES.txt | 1 +
.../apache/cassandra/gms/FailureDetector.java | 59 ++++++++++++++--
.../cassandra/utils/BoundedStatsDeque.java | 72 --------------------
.../gms/ArrayBackedBoundedStatsTest.java | 57 ++++++++++++++++
.../cassandra/utils/BoundedStatsDequeTest.java | 66 ------------------
5 files changed, 111 insertions(+), 144 deletions(-)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/cassandra/blob/ad8047ab/CHANGES.txt
----------------------------------------------------------------------
diff --git a/CHANGES.txt b/CHANGES.txt
index 6d031f6..753fb1c 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,4 +1,5 @@
2.0.16:
+ * ArrivalWindow should use primitives (CASSANDRA-9496)
* Periodically submit background compaction tasks (CASSANDRA-9592)
* Set HAS_MORE_PAGES flag to false when PagingState is null (CASSANDRA-9571)
* Backport indexed value validation fix from CASSANDRA-9057 (CASSANDRA-9564)
http://git-wip-us.apache.org/repos/asf/cassandra/blob/ad8047ab/src/java/org/apache/cassandra/gms/FailureDetector.java
----------------------------------------------------------------------
diff --git a/src/java/org/apache/cassandra/gms/FailureDetector.java b/src/java/org/apache/cassandra/gms/FailureDetector.java
index e247e48..8fdd99f 100644
--- a/src/java/org/apache/cassandra/gms/FailureDetector.java
+++ b/src/java/org/apache/cassandra/gms/FailureDetector.java
@@ -27,14 +27,12 @@ import java.util.concurrent.TimeUnit;
import javax.management.MBeanServer;
import javax.management.ObjectName;
-import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.cassandra.config.DatabaseDescriptor;
import org.apache.cassandra.io.FSWriteError;
import org.apache.cassandra.io.util.FileUtils;
-import org.apache.cassandra.utils.BoundedStatsDeque;
import org.apache.cassandra.utils.FBUtilities;
/**
@@ -289,11 +287,60 @@ public class FailureDetector implements IFailureDetector, FailureDetectorMBean
}
}
+/*
+ This class is not thread safe.
+ */
+class ArrayBackedBoundedStats
+{
+ private final long[] arrivalIntervals;
+ private long sum = 0;
+ private int index = 0;
+ private boolean isFilled = false;
+ private volatile double mean = 0;
+
+ public ArrayBackedBoundedStats(final int size)
+ {
+ arrivalIntervals = new long[size];
+ }
+
+ public void add(long interval)
+ {
+ if(index == arrivalIntervals.length)
+ {
+ isFilled = true;
+ index = 0;
+ }
+
+ if(isFilled)
+ sum = sum - arrivalIntervals[index];
+
+ arrivalIntervals[index++] = interval;
+ sum += interval;
+ mean = (double)sum / size();
+ }
+
+ private int size()
+ {
+ return isFilled ? arrivalIntervals.length : index;
+ }
+
+ public double mean()
+ {
+ return mean;
+ }
+
+ public long[] getArrivalIntervals()
+ {
+ return arrivalIntervals;
+ }
+
+}
+
class ArrivalWindow
{
private static final Logger logger = LoggerFactory.getLogger(ArrivalWindow.class);
private long tLast = 0L;
- private final BoundedStatsDeque arrivalIntervals;
+ private final ArrayBackedBoundedStats arrivalIntervals;
// this is useless except to provide backwards compatibility in phi_convict_threshold,
// because everyone seems pretty accustomed to the default of 8, and users who have
@@ -309,7 +356,7 @@ class ArrivalWindow
ArrivalWindow(int size)
{
- arrivalIntervals = new BoundedStatsDeque(size);
+ arrivalIntervals = new ArrayBackedBoundedStats(size);
}
private static long getMaxInterval()
@@ -355,14 +402,14 @@ class ArrivalWindow
// see CASSANDRA-2597 for an explanation of the math at work here.
double phi(long tnow)
{
- assert arrivalIntervals.size() > 0 && tLast > 0; // should not be called before any samples arrive
+ assert arrivalIntervals.mean() > 0 && tLast > 0; // should not be called before any samples arrive
long t = tnow - tLast;
return t / mean();
}
public String toString()
{
- return StringUtils.join(arrivalIntervals.iterator(), " ");
+ return Arrays.toString(arrivalIntervals.getArrivalIntervals());
}
}
http://git-wip-us.apache.org/repos/asf/cassandra/blob/ad8047ab/src/java/org/apache/cassandra/utils/BoundedStatsDeque.java
----------------------------------------------------------------------
diff --git a/src/java/org/apache/cassandra/utils/BoundedStatsDeque.java b/src/java/org/apache/cassandra/utils/BoundedStatsDeque.java
deleted file mode 100644
index 3983b74..0000000
--- a/src/java/org/apache/cassandra/utils/BoundedStatsDeque.java
+++ /dev/null
@@ -1,72 +0,0 @@
-/*
- * 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.utils;
-
-import java.util.Iterator;
-import java.util.NoSuchElementException;
-import java.util.concurrent.LinkedBlockingDeque;
-import java.util.concurrent.atomic.AtomicLong;
-import java.util.concurrent.atomic.AtomicReference;
-
-import com.google.common.util.concurrent.AtomicDouble;
-
-/**
- * bounded threadsafe deque
- */
-public class BoundedStatsDeque implements Iterable<Long>
-{
- private final LinkedBlockingDeque<Long> deque;
- private final AtomicLong sum;
-
- public BoundedStatsDeque(int size)
- {
- deque = new LinkedBlockingDeque<>(size);
- sum = new AtomicLong(0);
- }
-
- public Iterator<Long> iterator()
- {
- return deque.iterator();
- }
-
- public int size()
- {
- return deque.size();
- }
-
- public void add(long i)
- {
- if (!deque.offer(i))
- {
- Long removed = deque.remove();
- sum.addAndGet(-removed);
- deque.offer(i);
- }
- sum.addAndGet(i);
- }
-
- public long sum()
- {
- return sum.get();
- }
-
- public double mean()
- {
- return size() > 0 ? ((double) sum()) / size() : 0;
- }
-}
http://git-wip-us.apache.org/repos/asf/cassandra/blob/ad8047ab/test/unit/org/apache/cassandra/gms/ArrayBackedBoundedStatsTest.java
----------------------------------------------------------------------
diff --git a/test/unit/org/apache/cassandra/gms/ArrayBackedBoundedStatsTest.java b/test/unit/org/apache/cassandra/gms/ArrayBackedBoundedStatsTest.java
new file mode 100644
index 0000000..b6f4e07
--- /dev/null
+++ b/test/unit/org/apache/cassandra/gms/ArrayBackedBoundedStatsTest.java
@@ -0,0 +1,57 @@
+package org.apache.cassandra.gms;
+
+import java.util.Arrays;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+public class ArrayBackedBoundedStatsTest {
+
+ @Test
+ public void test()
+ {
+ int size = 4;
+
+ ArrayBackedBoundedStats bsd = new ArrayBackedBoundedStats(size);
+ //check the values for an empty result
+ assertEquals(0, bsd.mean(), 0.001d);
+
+ bsd.add(1L); //this one falls out, over limit
+ bsd.add(2L);
+ bsd.add(3L);
+ bsd.add(4L);
+ bsd.add(5L);
+
+ //verify that everything is in there
+ long [] expected = new long[] {2,3,4,5};
+ assertArrivalIntervals(bsd, expected);
+
+ //check results
+ assertEquals(3.5, bsd.mean(), 0.001d);
+ }
+
+ private void assertArrivalIntervals(ArrayBackedBoundedStats bsd, long [] expected)
+ {
+ Arrays.sort(expected);
+ Arrays.sort(bsd.getArrivalIntervals());
+ assertTrue(Arrays.equals(bsd.getArrivalIntervals(), expected));
+
+ }
+
+ @Test
+ public void testMultipleRounds() throws Exception
+ {
+ int size = 5;
+ ArrayBackedBoundedStats bsd = new ArrayBackedBoundedStats(size);
+
+ for(long i=0; i <= 1000;i++)
+ {
+ bsd.add(i);
+ }
+
+ long [] expected = new long[] {1000,999,998,997, 996};
+ assertArrivalIntervals(bsd, expected);
+ }
+}
http://git-wip-us.apache.org/repos/asf/cassandra/blob/ad8047ab/test/unit/org/apache/cassandra/utils/BoundedStatsDequeTest.java
----------------------------------------------------------------------
diff --git a/test/unit/org/apache/cassandra/utils/BoundedStatsDequeTest.java b/test/unit/org/apache/cassandra/utils/BoundedStatsDequeTest.java
deleted file mode 100644
index b64a765..0000000
--- a/test/unit/org/apache/cassandra/utils/BoundedStatsDequeTest.java
+++ /dev/null
@@ -1,66 +0,0 @@
-package org.apache.cassandra.utils;
-/*
- *
- * 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.
- *
- */
-
-
-import static org.junit.Assert.*;
-
-import java.util.Iterator;
-
-import org.junit.Test;
-
-public class BoundedStatsDequeTest
-{
- @Test
- public void test()
- {
- int size = 4;
-
- BoundedStatsDeque bsd = new BoundedStatsDeque(size);
- //check the values for an empty result
- assertEquals(0, bsd.size());
- assertEquals(0, bsd.sum(), 0.001d);
- assertEquals(0, bsd.mean(), 0.001d);
-
- bsd.add(1L); //this one falls out, over limit
- bsd.add(2L);
- bsd.add(3L);
- bsd.add(4L);
- bsd.add(5L);
-
- //verify that everything is in there
- Iterator<Long> iter = bsd.iterator();
- assertTrue(iter.hasNext());
- assertEquals(2L, iter.next(), 0);
- assertTrue(iter.hasNext());
- assertEquals(3L, iter.next(), 0);
- assertTrue(iter.hasNext());
- assertEquals(4L, iter.next(), 0);
- assertTrue(iter.hasNext());
- assertEquals(5L, iter.next(), 0);
- assertFalse(iter.hasNext());
-
- //check results
- assertEquals(size, bsd.size());
- assertEquals(14, bsd.sum(), 0.001d);
- assertEquals(3.5, bsd.mean(), 0.001d);
- }
-}