Hmmm, when I remove the concurrent abort, I am still seeing issues. This
time the first error I see is the following:
16:22:28,017 [1332957043@qtp-1797810984-15] ERROR com.ibm.team.jfs -
Originating Exception:
com.hp.hpl.jena.tdb.base.block.BlockException: No such block
at
com.hp.hpl.jena.tdb.base.recordbuffer.RecordRangeIterator.iterator(
RecordRangeIterator.java:39)
at com.hp.hpl.jena.tdb.index.bplustree.BPlusTree.iterator(
BPlusTree.java:378)
at
com.hp.hpl.jena.tdb.index.bplustree.BPlusTree.iterator(BPlusTree.java)
at com.hp.hpl.jena.tdb.index.TupleIndexRecord.findWorker(
TupleIndexRecord.java:164)
at com.hp.hpl.jena.tdb.index.TupleIndexRecord.findOrScan(
TupleIndexRecord.java:84)
at com.hp.hpl.jena.tdb.index.TupleIndexRecord.performFind(
TupleIndexRecord.java:78)
at com.hp.hpl.jena.tdb.index.TupleIndexBase.find(
TupleIndexBase.java:88)
at com.hp.hpl.jena.tdb.index.TupleTable.find(TupleTable.java:138)
at com.hp.hpl.jena.tdb.nodetable.NodeTupleTableConcrete.find(
NodeTupleTableConcrete.java:169)
at com.hp.hpl.jena.tdb.solver.StageMatchTuple.makeNextStage(
StageMatchTuple.java:101)
at com.hp.hpl.jena.tdb.solver.StageMatchTuple.makeNextStage(
StageMatchTuple.java:44)
at org.openjena.atlas.iterator.RepeatApplyIterator.hasNext(
RepeatApplyIterator.java:42)
at org.openjena.atlas.iterator.Iter$4.hasNext(Iter.java:274)
at
com.hp.hpl.jena.sparql.engine.iterator.QueryIterPlainWrapper.hasNextBinding(
QueryIterPlainWrapper.java:54)
at
com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(
QueryIteratorBase.java:107)
at
com.hp.hpl.jena.sparql.engine.iterator.QueryIterProcessBinding.hasNextBinding(
QueryIterProcessBinding.java:60)
at
com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(
QueryIteratorBase.java:107)
at
com.hp.hpl.jena.sparql.engine.iterator.QueryIterConvert.hasNextBinding(
QueryIterConvert.java:65)
at
com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(
QueryIteratorBase.java:107)
at
com.hp.hpl.jena.sparql.engine.iterator.QueryIterSlice.hasNextBinding(
QueryIterSlice.java:76)
at
com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(
QueryIteratorBase.java:107)
at
com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorWrapper.hasNextBinding(
QueryIteratorWrapper.java:40)
at
com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(
QueryIteratorBase.java:107)
at
com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorWrapper.hasNextBinding(
QueryIteratorWrapper.java:40)
at
com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(
QueryIteratorBase.java:107)
at com.hp.hpl.jena.sparql.engine.ResultSetStream.hasNext(
ResultSetStream.java:70)
at
com.ibm.team.jfs.rdf.internal.jenatdb.InternalResultSet.retrieveAllBindings(
InternalResultSet.java:46)
It must be something more fundamental :-(
From:
Simon Helsen/Toronto/IBM
To:
[email protected]
Date:
10/19/2011 03:26 PM
Subject:
Re: queryExecution.abort() and TxTDB transactions
Let me give me more detail how I set up the code. The main thread just
sets up the transaction, so, something like this:
DatasetGraphTxn dsGraph = null;
try {
dsGraph = StoreConnection.make(this.location
).begin(ReadWrite.READ);
Dataset ds = dsGraph.toDataset();
...
QueryExecution qe = null;
...
try {
results = qe.execSelect();
...
} finally {
if (qe != null) {
qe.close();
}
}
} catch (QueryCancelledException e) {
if (dsGraph != null) {
dsGraph.abort();
}
} finally {
if (dsGraph != null) {
dsGraph.close();
}
}
A parallel thread may decide that the given query needs to be cancelled,
so it has access to the QueryExecution and may decide to call
this.queryExecution.abort();
The question is whether I am just coding this wrong or whether there is
possible flow which does not yet work in TxTDB
thanks
Simon
From:
Simon Helsen/Toronto/IBM
To:
[email protected]
Date:
10/19/2011 03:18 PM
Subject:
queryExecution.abort() and TxTDB transactions
Hi guys,
is the interaction between queryExecution.abort() and TxTDB transactions
tested? When I use it, it seems that the store corrupts again. Note that
when the QueryCancellationException is thrown, I actively abort the
DatasetGraphTxn object, but I am seeing
14:59:20,580 [477961341@qtp-1709008349-8] WARN
hpl.jena.sparql.engine.iterator.QueryIteratorCheck - Open iterator:
QueryIterFilterExpr/37159
and then shortly after:
15:00:34,691 [jazz.jfs.indexer.jfs_tests_default_consumer_name.triple]
ERROR com.ibm.team.jfs - Originating
Exception:
com.hp.hpl.jena.tdb.base.file.FileException:
ObjectFile.read(8072)[12980][12980]: Impossibly large object : 1936010863
bytes
at com.hp.hpl.jena.tdb.base.objectfile.ObjectFileStorage.read(
ObjectFileStorage.java:294)
at
com.hp.hpl.jena.tdb.base.objectfile.ObjectFileStorage$ObjectIterator.next(
ObjectFileStorage.java:409)
etc.
Note that I call queryExecution.abort() in a separate thread and I wonder
if it runs in trouble if the main thread (executing the query) is just
calling queryExecution.close()
Simon
