DB2 - Problem description
Problem IT37047 | Status: Closed |
HANG DUE TO DEADLATCH BETWEEN VECTORIZEDADC THREAD AND NORMAL APPLICATION THREAD WHICH IS ROLLING BACK | |
product: | |
DB2 FOR LUW / DB2FORLUW / B50 - DB2 | |
Problem description: | |
A deadlatch can happen between a VectorizedADC thread and normal apphandle thread which is rolling back. This will cause the apphandle to hang and not be forced. The only way out is to recycle the Db2 instance. The stacks are: VectorizedADC thread: semop SQLO_SLATCH_CAS64::getConflict(unsigned long) sqlbfix(SQLB_FIX_CB*) sqlbSFVSFixPage(SQLB_FIX_CB*, int, unsigned int, int, bool*) ibm_cde::data::DatabaseTableAccessor::fixExistingPage(ibm_cde::d ata::PageRequest&, int) const ibm_cde::data::DatabaseTableAccessor::writeTableMetadata(unsigne d long, unsigned long, bool) ibm_cde::data::VectorizedADC::linkWriteAndEnableDictLocally(ibm_ cde::data::TableAccessor&) ibm_cde::data::VectorizedADC::buildDictionary(ibm_cde::data::Tab leAccessor&, bool, ADC_DICT_BUILD_SUMMARY*) ibm_cde::data::VectorizedADC::mergeHistogramsFromRPC(ibm_cde::da ta::TableAccessor&, ibm_cde::data::DataReader const&, unsigned long, short, bool, bool&, bool&) ibm_cde::data::VectADCPushHistogramsRPC::unmarshalReq(ibm_cde::d ata::RPCDataReader const&) ibm_cde::data::BaseRPC::receive(ibm_cde::data::RPCMessageHeader const&, ibm_cde::data::RPCDataReader const&, ibm_cde::data::RPCDataWriter&, ibm_cde::data::RPCReplyInfo&) ibm_cde::data::RPCReceiver::routeRPC(ibm_cde::data::RPCMessageHe ader const&, ibm_cde::data::RPCDataReader const&, ibm_cde::data::RPCDataWriter&, ibm_cde::data::RPCReplyInfo&) ibm_cde::data::RPCHandler::receiveReq(sqlrr_cb*, SQLKD_RQST_REPLY_FORMAT*, unsigned long, SQLR_RPCMESSAGE**, ibm_cde::data::RPCReplyInfo&) ibm_cde::data::cdeRPCHandlerInterface::receiveReq(sqlrr_cb*, SQLKD_RQST_REPLY_FORMAT*, unsigned long, SQLR_RPCMESSAGE**, ibm_cde::data::RPCReplyInfo&) sqlrr_rpc_router(sqlrr_cb*) This thread is holding: SAVEPOINTS latch and waiting on BPD latch The apphandle thread which has got the rollback request: __nanosleep sqloSpinLockConflict sqlpGetSPLatch(sqeAgent*, SQLP_SAVEPOINTS*, bool*, SQLP_SPTYPE) sqlpSpReq(sqeAgent*, SQLP_SPTYPE, unsigned long*) ibm_cde::data::Recovery::ScopedSavepoint::startSavepoint() ibm_cde::data::ExtendedInsertRangeList::createNewExtendedInsertR ange(ibm_cde::data::TableAccessor const&, ibm_cde::data::TableCache const&, ibm_cde::data::ExtendedInsertRangeRecord const&, ibm_cde::data::ExclusivePageRequest&) ibm_cde::data::DatabaseTableAccessor::writeTableStatistics(ibm_c de::data::TableStatisticsWriter&) ibm_cde::data::TableStatisticsWriter::writeTableStatistics(bool) ibm_cde::data::InsertRangeList::createExtendedInsertRangeIfNeces sary(unsigned long, ibm_cde::data::TableAccessor&, ibm_cde::data::TableAccessor*) ibm_cde::data::InsertRangeDistributor::reserveInsertRange(ibm_cd e::data::CDEApplication*, ibm_cde::data::TableAccessor&, ibm_cde::data::TableAccessor*, unsigned long) ibm_cde::data::CDEApplication::findOrReserveInsertRange(ibm_cde: :data::TableAccessor&, ibm_cde::data::TableAccessor*, unsigned long, bool&) ibm_cde::data::TableAccessor::associateWithInsertRange(ibm_cde:: data::TableAccessor*, unsigned long, bool&) ibm_cde::data::TableAccessor::setInsertRangeForCurrentApplicatio n(ibm_cde::data::TableAccessor*, unsigned long) ibm_cde::data::TableAccessor::setInsertRangeForCurrentApplicatio n(ibm_cde::data::TableAccessorAllocator*, unsigned long) ibm_cde::query::Scheduler::prepInsertUpdateSTQ(ibm_cde::query::S yntaxTree*) This thread is holding the BPD latch and waiting on SAVEPOINTS latch. | |
Problem Summary: | |
**************************************************************** * USERS AFFECTED: * * ALL * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Upgrade to 11.5 FP7 or later * **************************************************************** | |
Local Fix: | |
Solution | |
Workaround | |
**************************************************************** * USERS AFFECTED: * * ALL * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Upgrade to 11.5 FP7 or later * **************************************************************** | |
Comment | |
Upgrade to 11.5 FP7 or later | |
Timestamps | |
Date - problem reported : Date - problem closed : Date - last modified : | 27.05.2021 21.11.2021 21.11.2021 |
Problem solved at the following versions (IBM BugInfos) | |
Problem solved according to the fixlist(s) of the following version(s) |