The diskstat table provides information about writes to Disk Data tablespaces during the past 1 second.
The diskstat table contains the following columns:
node_id
Node ID of this node
block_instance
ID of reporting instance of PGMAN
pages_made_dirty
Number of pages made dirty during the past second
reads_issued
Reads issued during the past second
reads_completed
Reads completed during the past second
writes_issued
Writes issued during the past second
writes_completed
Writes completed during the past second
log_writes_issued
Number of times a page write has required a log write during the past second
log_writes_completed
Number of log writes completed during the last second
get_page_calls_issued
Number of get_page() calls issued during the past second
get_page_reqs_issued
Number of times that a get_page() call has resulted in a wait for I/O or completion of I/O already begun during the past second
get_page_reqs_completed
Number of get_page() calls waiting for I/O or I/O completion that have completed during the past second
Each row in this table corresponds to an instance of PGMAN; there is one such instance per LDM thread plus an additional instance for each data node.
The diskstat table was added in NDB 8.0.19.