NDB Cluster Configuration Files SET_VAR  Hint Applies No Type Boolean Default Value ON Command-Line Format --ndb-batch-size System Variable ndb_batch_size Scope Global Dynamic No SET_VAR  Hint Applies No Type Integer Default Value 32768 Minimum Value 0 Maximum Value 31536000 Command-Line Format --ndb-cluster-connection-pool System Variable ndb_cluster_connection_pool System Variable ndb_cluster_connection_pool Scope Global Scope Global Dynamic No Dynamic No SET_VAR  Hint Applies No SET_VAR  Hint Applies No Type Integer Default Value 1 Minimum Value 1 Maximum Value 63 • --ndb-batch-size= # Let  ALTER TABLE  and other DDL statements use copying operations on  NDB  tables. Set to  OFF  to keep this from happening; doing so may improve performance of critical applications. This sets the size in bytes that is used for NDB transaction batches. • --ndb-cluster-connection-pool= # By setting this option to a value greater than 1 (the default), a  mysqld  process can use multiple connections to the cluster, effectively mimicking several SQL nodes. Each connection requires its own [api]  or  [mysqld]  section in the cluster configuration ( config.ini ) file, and counts against the maximum number of API connections supported by the cluster. Suppose that you have 2 cluster host computers, each running an SQL node whose  mysqld  process was started with  --ndb-cluster-connection-pool=4 ; this means that the cluster must have 8 API slots available for these connections (instead of 2). All of these connections are set up when the SQL node connects to the cluster, and are allocated to threads in a round-robin fashion. 4162