Author: aadamchik
Date: Fri Jun 16 07:37:38 2006
New Revision: 414839
URL: http://svn.apache.org/viewvc?rev=414839&view=rev
Log:
IncrementalFaultList deadlock fix.
When connection pool size is less than the number of concurrent requests, doing
commit and filling in IncrementalFaultList in parallel eventually causes a
deadlock.
IncrementalFaultList is holding an open connection and trying to get a lock on
DataRowStore, while a committing thread that locked DataRowStore can's get a
connection,
cause the pool is empty.
(I can't log in to Jira due to Apache network problems; I will enter the bug
once this is resolved)
Modified:
incubator/cayenne/main/trunk/cayenne/cayenne-java/src/cayenne/java/org/objectstyle/cayenne/access/IncrementalFaultList.java
Modified:
incubator/cayenne/main/trunk/cayenne/cayenne-java/src/cayenne/java/org/objectstyle/cayenne/access/IncrementalFaultList.java
URL:
http://svn.apache.org/viewvc/incubator/cayenne/main/trunk/cayenne/cayenne-java/src/cayenne/java/org/objectstyle/cayenne/access/IncrementalFaultList.java?rev=414839&r1=414838&r2=414839&view=diff
==============================================================================
---
incubator/cayenne/main/trunk/cayenne/cayenne-java/src/cayenne/java/org/objectstyle/cayenne/access/IncrementalFaultList.java
(original)
+++
incubator/cayenne/main/trunk/cayenne/cayenne-java/src/cayenne/java/org/objectstyle/cayenne/access/IncrementalFaultList.java
Fri Jun 16 07:37:38 2006
@@ -221,6 +221,7 @@
rowWidth = 0;
try {
+ int lastResolved = 0;
long t1 = System.currentTimeMillis();
ResultIterator it = dataContext.performIteratedQuery(query);
try {
@@ -230,20 +231,12 @@
// resolve first page if we can
if (resolvesFirstPage()) {
// read first page completely, the rest as ObjectIds
- List firstPage = (fetchesDataRows) ? elements : new
ArrayList(
- pageSize);
for (int i = 0; i < pageSize && it.hasNextRow(); i++) {
- firstPage.add(it.nextDataRow());
+ elements.add(it.nextDataRow());
+ lastResolved++;
}
- // convert rows to objects
- if (!fetchesDataRows) {
- elements.addAll(dataContext.objectsFromDataRows(
- rootEntity,
- firstPage,
- info.isRefreshingObjects(),
- info.isResolvingInherited()));
- }
+ // defer DataRows -> Objects conversion till we are
completely done.
}
// continue reading ids
@@ -255,10 +248,23 @@
QueryLogger.logSelectCount(elements.size(), System
.currentTimeMillis()
- t1);
-
}
finally {
it.close();
+ }
+
+ // fill in the first page AFTER the iterator was closed,
otherwise we may
+ // cause an (unobvious) deadlock due to connection pool
exhaustion
+ if (!fetchesDataRows && lastResolved > 0) {
+ List objects = dataContext.objectsFromDataRows(
+ rootEntity,
+ elements.subList(0, lastResolved),
+ info.isRefreshingObjects(),
+ info.isResolvingInherited());
+
+ for(int i = 0; i < lastResolved; i++) {
+ elements.set(i, objects.get(i));
+ }
}
}
catch (CayenneException e) {
