2550309 - Secondary node crashed with s_bufman::PrivateFlush -- SAP IQ

Secondary server may fail with following fatal stack trace frames and diagnostic messages in .iqmsg.

---
s_bufman::PrivateFlush
s_bufman::FlushToDisk
st_txncb::FlushCoalesce
st_txncb::FlushForCommit
st_txnMgr::FlushForCommit
st_command::DoCmdThroughResourceGate
st_iqtxn::FlushForCommit
UIQTxn_FlushForCommit
st_SAIQInterfaceInfo::callFunction
st_SAIQInterface::RunIQFunc
st_SAIQInterface::Execute
saint_iqthresholdtxn::FlushForCommit
ri_commit
Connection::commit_work
_ri_auto_commit
iq_alter_mpxversionlist
dbi_iq_alter_mpxserver
DoExecuteStmt
db__execute_str
Connection::ExecMpxRPC
sp_iqmpxddlrunas2_internal
RunInternalProcedure
process_ext_int_remote_call

---

blockmap userlocked during flush; _blockmap @ 0x7ffb441b8b88
Blockmap Member Variables for 0x7ffb441b8b88
From dblib/db_table.cxx:3052
   _nextPartitionForHelperFlush = 0
                   IsEBufNoWait = 0
                IsProxyFreelist = 0
                 _OrigRootBlock = 811132169
                           _Bio = 0x7ffbec15fe48
                     _tempSpace = 0
                        _Bufman = 0x7ffbec041808 main Bufman
             _allocFromLastLink = 1
                        _isMeta = 1
                   _m_dbspaceID = 16387
                     _dbspaceID = 16387
                   _rangePIDmap = 0
                 _useGlobalLBNs = 0
            _isDistributedOwner = 0
                     _LBNOffset = 1
                       _LBNBase = 1
                 _nextGlobalLBN = 1
                      _RWAccess = 1
                   _gotIdentity = 0
      _gotIdentityWithNoEntries = 0
           _allocationPrivilege = 0
                      _pageInfo = 0x7ffb440addc8
                  _perConnStats = 0x7ffb441ba3d8
               _tmp_rangePIDmap = 0
               _nPhysicalWrites = 0
                _nPhysicalReads = 0
                  _LockRefCount = 1
              _PrefetchRefCount = 0
              _ScanModeRefCount = 0
                     _DirtyList = 0x7ffb46290b88
               #DirtyReferences = 0
                    #DirtyLinks = 0
                         _pnext = 0x7ffb441d09f8
                         _pprev = 0x7ffb440efb08
                     _cacheSize = 0
                         _cache = 0
                         _nBlks = 0
               _leaderCxtCursor = 0
                   _allowToFree = 0
                        _psuAll = 0
[s_blockmap_identity]
_UniqueId: 223906773
_RootBlockId: 811132169
_NEntries: 4
_LastWriterTxnId: 329626921
_LastWriterSavePoint: 1
_FanOutAndFlags2: 0x8
_Flags: 0xcd
_Version: 1
_NLinks: 1
_EntriesPerLink: 19959
_FirstAvailLink: 0
_MaxLink: 1
_ModNum: 4
_RootModNum: 3
[end s_blockmap_identity]
**************************************************
***   SAP IQ Abort:
***      From:  slib/s_bufman.cxx:5506
***      PID: 26564
***      Message: blockmap userlocked during flush
***      Thread: 140715162830592  (TID: 56)
**************************************************

IQ 16 sp11 pl11+

slib/s_bufman.cxx:5506 , blockmap userlocked , s_blockmap_identity , s_bufman::PrivateFlush , s_bufman::FlushToDisk , st_txncb::FlushCoalesce , iq_alter_mpxversionlist , dbi_iq_alter_mpxserver , Connection::ExecMpxRPC , KBA , BC-SYB-IQ , Sybase IQ , Bug Filed