Overview of NDB Cluster Configuration Parameters, Options, and Variables • LogLevelNodeRestart : Level of node restart and node failure information printed to stdout. • LogLevelShutdown : Level of node shutdown information printed to stdout. • LogLevelStartup : Level of node startup information printed to stdout. • LogLevelStatistic : Level of transaction, operation, and transporter information printed to stdout. • LongMessageBuffer : Number of bytes allocated on each data node for internal long messages. • MaxAllocate : No longer used; has no effect. • MaxBufferedEpochs : Allowed numbered of epochs that subscribing node can lag behind (unprocessed epochs). Exceeding causes lagging subscribers to be disconnected. • MaxBufferedEpochBytes : Total number of bytes allocated for buffering epochs. • MaxDiskDataLatency : Maximum allowed mean latency of disk access (ms) before starting to abort transactions. • MaxDiskWriteSpeed : Maximum number of bytes per second that can be written by LCP and backup when no restarts are ongoing. • MaxDiskWriteSpeedOtherNodeRestart : Maximum number of bytes per second that can be written by LCP and backup when another node is restarting. • MaxDiskWriteSpeedOwnRestart : Maximum number of bytes per second that can be written by LCP and backup when this node is restarting. • MaxFKBuildBatchSize : Maximum scan batch size to use for building foreign keys. Increasing this value may speed up builds of foreign keys but impacts ongoing traffic as well. • MaxDMLOperationsPerTransaction : Limit size of transaction; aborts transaction if it requires more than this many DML operations. Set to 0 to disable. • MaxLCPStartDelay : Time in seconds that LCP polls for checkpoint mutex (to allow other data nodes to complete metadata synchronization), before putting itself in lock queue for parallel recovery of table data. • MaxNoOfAttributes : Suggests total number of attributes stored in database (sum over all tables). • MaxNoOfConcurrentIndexOperations : Total number of index operations that can execute simultaneously on one data node. • MaxNoOfConcurrentOperations : Maximum number of operation records in transaction coordinator. • MaxNoOfConcurrentScans : Maximum number of scans executing concurrently on data node. • MaxNoOfConcurrentSubOperations : Maximum number of concurrent subscriber operations. • MaxNoOfConcurrentTransactions : Maximum number of transactions executing concurrently on this data node, total number of transactions that can be executed concurrently is this value times number of data nodes in cluster. • MaxNoOfFiredTriggers : Total number of triggers that can fire simultaneously on one data node. • MaxNoOfLocalOperations : Maximum number of operation records defined on this data node. • MaxNoOfLocalScans : Maximum number of fragment scans in parallel on this data node. • MaxNoOfOpenFiles : Maximum number of files open per data node.(One thread is created per file). 4035