Author: jbellis
Date: Mon Sep 12 15:50:16 2011
New Revision: 1169807
URL: http://svn.apache.org/viewvc?rev=1169807&view=rev
Log:
remove allocator.size() from Memtable.getLiveSize calculation
patch by jbellis and stuhood for CASSANDRA-3168
Modified:
cassandra/branches/cassandra-1.0.0/CHANGES.txt
cassandra/branches/cassandra-1.0.0/NEWS.txt
cassandra/branches/cassandra-1.0.0/src/java/org/apache/cassandra/db/Memtable.java
cassandra/branches/cassandra-1.0.0/src/java/org/apache/cassandra/utils/SlabAllocator.java
Modified: cassandra/branches/cassandra-1.0.0/CHANGES.txt
URL:
http://svn.apache.org/viewvc/cassandra/branches/cassandra-1.0.0/CHANGES.txt?rev=1169807&r1=1169806&r2=1169807&view=diff
==============================================================================
--- cassandra/branches/cassandra-1.0.0/CHANGES.txt (original)
+++ cassandra/branches/cassandra-1.0.0/CHANGES.txt Mon Sep 12 15:50:16 2011
@@ -67,7 +67,7 @@
* fix inconsistency of the CLI syntax when {} should be used instead of [{}]
(CASSANDRA-3119)
* rename CQL type names to match expected SQL behavior (CASSANDRA-3149, 3031)
- * Arena-based allocation for memtables (CASSANDRA-2252, 3162, 3163)
+ * Arena-based allocation for memtables (CASSANDRA-2252, 3162, 3163, 3168)
* Default RR chance to 0.1 (CASSANDRA-3169)
Modified: cassandra/branches/cassandra-1.0.0/NEWS.txt
URL:
http://svn.apache.org/viewvc/cassandra/branches/cassandra-1.0.0/NEWS.txt?rev=1169807&r1=1169806&r2=1169807&view=diff
==============================================================================
--- cassandra/branches/cassandra-1.0.0/NEWS.txt (original)
+++ cassandra/branches/cassandra-1.0.0/NEWS.txt Mon Sep 12 15:50:16 2011
@@ -11,6 +11,9 @@ Upgrading
- CQL types bytea and date were renamed to blob and timestamp,
respectively,
to conform with SQL norms. CQL type int is now a 4-byte int, not 8
(which is still available as bigint).
+ - Cassandra 1.0 uses arena allocation to reduce old generation
fragmentation.
+ This means there is a minimum overhead of 1MB per ColumnFamily plus
+ 1MB per index.
Features
--------
Modified:
cassandra/branches/cassandra-1.0.0/src/java/org/apache/cassandra/db/Memtable.java
URL:
http://svn.apache.org/viewvc/cassandra/branches/cassandra-1.0.0/src/java/org/apache/cassandra/db/Memtable.java?rev=1169807&r1=1169806&r2=1169807&view=diff
==============================================================================
---
cassandra/branches/cassandra-1.0.0/src/java/org/apache/cassandra/db/Memtable.java
(original)
+++
cassandra/branches/cassandra-1.0.0/src/java/org/apache/cassandra/db/Memtable.java
Mon Sep 12 15:50:16 2011
@@ -90,7 +90,7 @@ public class Memtable
{
// 25% fudge factor on the base throughput * liveRatio calculation.
(Based on observed
// pre-slabbing behavior -- not sure what accounts for this. May have
changed with introduction of slabbing.)
- return (long) (currentThroughput.get() * cfs.liveRatio * 1.25) +
allocator.size();
+ return (long) (currentThroughput.get() * cfs.liveRatio * 1.25);
}
public long getSerializedSize()
Modified:
cassandra/branches/cassandra-1.0.0/src/java/org/apache/cassandra/utils/SlabAllocator.java
URL:
http://svn.apache.org/viewvc/cassandra/branches/cassandra-1.0.0/src/java/org/apache/cassandra/utils/SlabAllocator.java?rev=1169807&r1=1169806&r2=1169807&view=diff
==============================================================================
---
cassandra/branches/cassandra-1.0.0/src/java/org/apache/cassandra/utils/SlabAllocator.java
(original)
+++
cassandra/branches/cassandra-1.0.0/src/java/org/apache/cassandra/utils/SlabAllocator.java
Mon Sep 12 15:50:16 2011
@@ -29,6 +29,8 @@ import java.util.concurrent.atomic.Atomi
import com.google.common.base.Preconditions;
import com.google.common.collect.Iterables;
import com.google.common.collect.MapMaker;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
/**
* The SlabAllocator is a bump-the-pointer allocator that allocates
@@ -46,24 +48,13 @@ import com.google.common.collect.MapMake
*/
public class SlabAllocator extends Allocator
{
+ private static Logger logger =
LoggerFactory.getLogger(SlabAllocator.class);
+
private final static int REGION_SIZE = 1024 * 1024;
private final static int MAX_CLONED_SIZE = 128 * 1024; // bigger than this
don't go in the region
private final AtomicReference<Region> currentRegion = new
AtomicReference<Region>();
- private final Collection<Region> filledRegions =
Collections.newSetFromMap(new MapMaker().weakKeys().<Region, Boolean>makeMap());
-
- /** @return Total number of bytes allocated by this allocator. */
- public long size()
- {
- Iterable<Region> regions = filledRegions;
- if (currentRegion.get() != null)
- regions = Iterables.concat(regions,
Collections.<Region>singleton(currentRegion.get()));
-
- long total = 0;
- for (Region region : regions)
- total += region.size;
- return total;
- }
+ private volatile int regionCount;
public ByteBuffer allocate(int size)
{
@@ -86,23 +77,11 @@ public class SlabAllocator extends Alloc
return cloned;
// not enough space!
- tryRetireRegion(region);
+ currentRegion.compareAndSet(region, null);
}
}
/**
- * Try to retire the current region if it is still <code>region</code>.
- * Postcondition is that curRegion.get() != region
- */
- private void tryRetireRegion(Region region)
- {
- if (currentRegion.compareAndSet(region, null))
- {
- filledRegions.add(region);
- }
- }
-
- /**
* Get the current region, or, if there is no current region, allocate a
new one
*/
private Region getRegion()
@@ -122,6 +101,8 @@ public class SlabAllocator extends Alloc
{
// we won race - now we need to actually do the expensive
allocation step
region.init();
+ regionCount++;
+ logger.debug("{} regions now allocated in {}", regionCount,
this);
return region;
}
// someone else won race - that's fine, we'll try to grab theirs
