NDB Cluster supports storing nonindexed columns of
NDB tables on disk, rather than in
RAM. Column data and logging metadata are kept in data files and
undo log files, conceptualized as tablespaces and log file groups,
as described in the next section—see
Section 220.127.116.11, “NDB Cluster Disk Data Objects”.
NDB Cluster Disk Data performance can be influenced by a number of configuration parameters. For information about these parameters and their effects, see Disk Data Configuration Parameters, and Disk Data and GCP Stop errors.
The performance of an NDB Cluster that uses Disk Data storage can
also be greatly improved by separating data node file systems from
undo log files and tablespace data files, which can be done using
symbolic links. For more information, see
Section 18.104.22.168, “Using Symbolic Links with Disk Data Objects”. Beginning with
NDB 8.0.19, you should also set the
node configuration parameter to
using separate disks for Disk Data files.
NDB 8.0.19 (and later) provides improved support when using Disk Data tables with solid-state drives, in particular those using NVMe. See the following documentation for more information: