svn commit: r1002589 - /jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/state/ItemStateReferenceCache.java

[ju...@apache.org]

Author: jukka
Date: Wed Sep 29 12:28:42 2010
New Revision: 1002589

URL: http://svn.apache.org/viewvc?rev=1002589&view=rev
Log:
JCR-2699: Improve read/write concurrency

Revert back to weak references in ItemStateReferenceCache as using soft references seems to cause notable performance drop in the TCK test run

Modified:
    jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/state/ItemStateReferenceCache.java

Modified: jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/state/ItemStateReferenceCache.java
URL: http://svn.apache.org/viewvc/jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/state/ItemStateReferenceCache.java?rev=1002589&r1=1002588&r2=1002589&view=diff
==============================================================================
--- jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/state/ItemStateReferenceCache.java (original)
+++ jackrabbit/trunk/jackrabbit-core/src/main/java/org/apache/jackrabbit/core/state/ItemStateReferenceCache.java Wed Sep 29 12:28:42 2010
@@ -54,7 +54,12 @@ public class ItemStateReferenceCache imp
      */
     @SuppressWarnings("unchecked")
     private final Map<ItemId, ItemState> refs =
-        new ReferenceMap(ReferenceMap.HARD, ReferenceMap.SOFT);
+        // I tried using soft instead of weak references here, but that
+        // seems to have some unexpected performance consequences (notable
+        // increase in the JCR TCK run time). So even though soft references
+        // are generally recommended over weak references for caching
+        // purposes, it seems that using weak references is safer here.
+        new ReferenceMap(ReferenceMap.HARD, ReferenceMap.WEAK);
 
     /**
      * secondary cache that automatically flushes entries based on some