6.16.31 The ndbinfo diskstat Table

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

Notes

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.