Author: jbellis
Date: Mon Dec 20 04:31:04 2010
New Revision: 1050981
URL: http://svn.apache.org/viewvc?rev=1050981&view=rev
Log:
Re-cache hotkeys post-compaction without hitting disk
patch by jbellis; reviewed by tjake for CASSANDRA-1878
Modified:
cassandra/branches/cassandra-0.6/CHANGES.txt
cassandra/branches/cassandra-0.6/src/java/org/apache/cassandra/db/CompactionManager.java
cassandra/branches/cassandra-0.6/src/java/org/apache/cassandra/io/SSTableReader.java
Modified: cassandra/branches/cassandra-0.6/CHANGES.txt
URL:
http://svn.apache.org/viewvc/cassandra/branches/cassandra-0.6/CHANGES.txt?rev=1050981&r1=1050980&r2=1050981&view=diff
==============================================================================
--- cassandra/branches/cassandra-0.6/CHANGES.txt (original)
+++ cassandra/branches/cassandra-0.6/CHANGES.txt Mon Dec 20 04:31:04 2010
@@ -25,6 +25,7 @@
* large row support for SSTableExport (CASSANDRA-1867)
* return InvalidRequest when remove of subcolumn without supercolumn
is requested (CASSANDRA-1866)
+ * Re-cache hot keys post-compaction without hitting disk (CASSANDRA-1878)
0.6.8
Modified:
cassandra/branches/cassandra-0.6/src/java/org/apache/cassandra/db/CompactionManager.java
URL:
http://svn.apache.org/viewvc/cassandra/branches/cassandra-0.6/src/java/org/apache/cassandra/db/CompactionManager.java?rev=1050981&r1=1050980&r2=1050981&view=diff
==============================================================================
---
cassandra/branches/cassandra-0.6/src/java/org/apache/cassandra/db/CompactionManager.java
(original)
+++
cassandra/branches/cassandra-0.6/src/java/org/apache/cassandra/db/CompactionManager.java
Mon Dec 20 04:31:04 2010
@@ -281,6 +281,8 @@ public class CompactionManager implement
Iterator<CompactionIterator.CompactedRow> nni = new FilterIterator(ci,
PredicateUtils.notNullPredicate());
executor.beginCompaction(cfs, ci);
+ Map<DecoratedKey, SSTable.PositionSize> cachedKeys = new
HashMap<DecoratedKey, SSTable.PositionSize>();
+
try
{
if (!nni.hasNext())
@@ -306,6 +308,15 @@ public class CompactionManager implement
if (rowsize > DatabaseDescriptor.getRowWarningThreshold())
logger.warn("Large row " + row.key.key + " in " +
cfs.getColumnFamilyName() + " " + rowsize + " bytes");
cfs.addToCompactedRowStats(rowsize);
+
+ for (SSTableReader sstable : sstables)
+ {
+ if (sstable.getCachedPosition(row.key) != null)
+ {
+ cachedKeys.put(row.key, new
SSTable.PositionSize(prevpos, rowsize));
+ break;
+ }
+ }
}
}
finally
@@ -315,6 +326,8 @@ public class CompactionManager implement
SSTableReader ssTable = writer.closeAndOpenReader();
cfs.replaceCompactedSSTables(sstables, Arrays.asList(ssTable));
+ for (Entry<DecoratedKey, SSTable.PositionSize> entry :
cachedKeys.entrySet())
+ ssTable.cacheKey(entry.getKey(), entry.getValue());
submitMinorIfNeeded(cfs);
String format = "Compacted to %s. %d/%d bytes for %d keys. Time:
%dms";
Modified:
cassandra/branches/cassandra-0.6/src/java/org/apache/cassandra/io/SSTableReader.java
URL:
http://svn.apache.org/viewvc/cassandra/branches/cassandra-0.6/src/java/org/apache/cassandra/io/SSTableReader.java?rev=1050981&r1=1050980&r2=1050981&view=diff
==============================================================================
---
cassandra/branches/cassandra-0.6/src/java/org/apache/cassandra/io/SSTableReader.java
(original)
+++
cassandra/branches/cassandra-0.6/src/java/org/apache/cassandra/io/SSTableReader.java
Mon Dec 20 04:31:04 2010
@@ -323,6 +323,23 @@ public class SSTableReader extends SSTab
}
}
+ public void cacheKey(DecoratedKey key, PositionSize info)
+ {
+ keyCache.put(new Pair<String, DecoratedKey>(path, key), info);
+ }
+
+ public PositionSize getCachedPosition(DecoratedKey key)
+ {
+ return getCachedPosition(new Pair<String, DecoratedKey>(path, key));
+ }
+
+ private PositionSize getCachedPosition(Pair<String, DecoratedKey>
unifiedKey)
+ {
+ if (keyCache != null && keyCache.getCapacity() > 0)
+ return keyCache.get(unifiedKey);
+ return null;
+ }
+
/**
* returns the position in the data file to find the given key, or -1 if
the key is not present
*/
@@ -334,14 +351,9 @@ public class SSTableReader extends SSTab
// next, the key cache
Pair<String, DecoratedKey> unifiedKey = new Pair<String,
DecoratedKey>(path, decoratedKey);
- if (keyCache != null && keyCache.getCapacity() > 0)
- {
- PositionSize cachedPosition = keyCache.get(unifiedKey);
- if (cachedPosition != null)
- {
- return cachedPosition;
- }
- }
+ PositionSize cachedPosition = getCachedPosition(unifiedKey);
+ if (cachedPosition != null)
+ return cachedPosition;
// next, see if the sampled index says it's impossible for the key to
be present
IndexSummary.KeyPosition sampledPosition =
getIndexScanPosition(decoratedKey);
