MySQL 8.4 Reference Manual Including MySQL NDB Cluster 8.4
The logbuffer table provides information on
NDB Cluster log buffer usage.
The logbuffers table contains the following
columns:
node_id
The ID of this data node.
log_type
Type of log. One of: REDO,
DD-UNDO, BACKUP-DATA,
or BACKUP-LOG.
log_id
The log ID; for Disk Data undo log files, this is the same
as the value shown in the
LOGFILE_GROUP_NUMBER column of the
Information Schema FILES table
as well as the value shown for the log_id
column of the ndbinfo
logspaces table
log_part
The log part number
total
Total space available for this log
used
Space used by this log
logbuffers table rows reflecting two
additional log types are available when performing an NDB
backup. One of these rows has the log type
BACKUP-DATA, which shows the amount of data
buffer used during backup to copy fragments to backup files. The
other row has the log type BACKUP-LOG, which
displays the amount of log buffer used during the backup to
record changes made after the backup has started. One each of
these log_type rows is shown in the
logbuffers table for each data node in the
cluster. These rows are not present unless an NDB backup is
currently being performed.