Hi Andy, I'll dig a little deeper into what's going on and will put together a reproducible test case for this. I first wanted to find out if it might be something obvious.
Thanks, Aaron On Wed, 15 Jan 2020 at 13:44, Andy Seaborne <a...@apache.org> wrote: > Hi Aaron, > > Could you say some more about how the concurrent writes are happening > and what they are doing? Just from the stacktrace I haven't managed to > write a test case. > > My guess is that another transaction is finishing a commit about the > same time. But if the other transaction is mid-processing then its > something else. > > If you are able to putting in a JVM-suspend breakpoint at > ThreadBufferingCache:88 and capture a thread dump, that would be very > helpful - I realise it's not always easy to get up. > > Andy > > > > On 15/01/2020 16:55, Aaron Coburn wrote: > > This might be good to split off into a separate issue (and it doesn't > > necessarily need to block the release), but I'm finding that, when using > > TDB2 with this release candidate in a concurrent write context, I start > > encountering a lot of errors. And those errors are definitely not present > > with 3.13.1. Specifically, the issue seems to be related to contention > over > > the TDB2 ThreadBufferingCache. That buffering cache is present in the > > 3.13.1 release, and I'm not entirely sure what changed with 3.14.0 that > > would trigger these errors, but this is the relevant part of the stack > > trace: > > > > Caused by: org.apache.jena.tdb2.TDBException: ThreadBufferingCache: > already > > buffering > > at > > > org.apache.jena.tdb2.store.nodetable.ThreadBufferingCache.enableBuffering(ThreadBufferingCache.java:88) > > at > > > org.apache.jena.tdb2.store.nodetable.NodeTableCache.updateStart(NodeTableCache.java:352) > > at > > > org.apache.jena.tdb2.store.nodetable.NodeTableCache.notifyTxnStart(NodeTableCache.java:319) > > at > > > org.apache.jena.dboe.transaction.txn.TransactionCoordinator.lambda$notifyBegin$14(TransactionCoordinator.java:915) > > at > > > org.apache.jena.dboe.transaction.txn.TransactionCoordinator.lambda$listeners$0(TransactionCoordinator.java:207) > > at java.base/java.util.ArrayList.forEach(ArrayList.java:1540) > > at > > > org.apache.jena.dboe.transaction.txn.TransactionCoordinator.listeners(TransactionCoordinator.java:207) > > at > > > org.apache.jena.dboe.transaction.txn.TransactionCoordinator.notifyBegin(TransactionCoordinator.java:915) > > at > > > org.apache.jena.dboe.transaction.txn.TransactionCoordinator.begin(TransactionCoordinator.java:553) > > at > > > org.apache.jena.dboe.transaction.txn.TransactionCoordinator.begin(TransactionCoordinator.java:509) > > at > > > org.apache.jena.dboe.transaction.txn.TransactionalBase.begin(TransactionalBase.java:110) > > at > > > org.apache.jena.dboe.storage.system.DatasetGraphStorage.begin(DatasetGraphStorage.java:59) > > at > > > org.apache.jena.sparql.core.DatasetGraphWrapper.begin(DatasetGraphWrapper.java:233) > > at org.apache.jena.sparql.core.DatasetImpl.begin(DatasetImpl.java:116) > > at org.apache.jena.system.Txn.exec(Txn.java:76) > > at org.apache.jena.system.Txn.executeWrite(Txn.java:125) > > at > > > org.apache.jena.rdfconnection.RDFConnectionLocal.update(RDFConnectionLocal.java:80) > > > > Effectively, I get that error at the first time a client attempts to > > concurrently write to the TDB2 store. Subsequent attempts just hang. > > > > Cheers, > > Aaron > > > > > > > > > > > > On Mon, 13 Jan 2020 at 11:23, Andy Seaborne <a...@apache.org> wrote: > > > >> Hi, > >> > >> Here is a vote on the release of Apache Jena 3.14.0 > >> This is the first proposed release candidate. > >> > >> ==== Changes: > >> > >> https://s.apache.org/jena-3.14.0-jira > >> > >> ==== Release Vote > >> > >> Everyone, not just committers, is invited to test and vote. > >> Please download and test the proposed release. > >> > >> Staging repository: > >> > https://repository.apache.org/content/repositories/orgapachejena-1035 > >> > >> Proposed dist/ area: > >> https://dist.apache.org/repos/dist/dev/jena/ > >> > >> Keys: > >> https://svn.apache.org/repos/asf/jena/dist/KEYS > >> > >> Git commit (browser URL): > >> https://github.com/apache/jena/commit/19d42a5 > >> > >> Git Commit Hash: > >> 19d42a57a9debc675047b2d1ce9769979c43e7d8 > >> > >> Git Commit Tag: > >> jena-3.14.0 > >> > >> Please vote to approve this release: > >> > >> [ ] +1 Approve the release > >> [ ] 0 Don't care > >> [ ] -1 Don't release, because ... > >> > >> This vote will be open until at least > >> > >> Thursday, 16th January 2020 at 187:00 UTC > >> > >> If you expect to check the release but the time limit does not work > >> for you, please email within the schedule above with an expected time > >> and we can extend the vote period. > >> > >> Thanks, > >> > >> Andy > >> > >> Checking needed: > >> > >> + are the GPG signatures fine? > >> + are the checksums correct? > >> + is there a source archive? > >> > >> + can the source archive really be built? > >> (NB This requires a "mvn install" first time) > >> + is there a correct LICENSE and NOTICE file in each artifact > >> (both source and binary artifacts)? > >> + does the NOTICE file contain all necessary attributions? > >> + have any licenses of dependencies changed due to upgrades? > >> if so have LICENSE and NOTICE been upgraded appropriately? > >> + does the tag/commit in the SCM contain reproducible sources? > >> > > >