25.6.17.33 The ndbinfo diskstats_1sec Table

The diskstats_1sec table provides information about writes to Disk Data tablespaces over the past 20 seconds.

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

  Pages made dirty during the designated 1-second interval

• reads_issued

  Reads issued during the designated 1-second interval

• reads_completed

  Reads completed during the designated 1-second interval

• writes_issued

  Writes issued during the designated 1-second interval

• writes_completed

  Writes completed during the designated 1-second interval

• log_writes_issued

  Number of times a page write has required a log write during the designated 1-second interval

• log_writes_completed

  Number of log writes completed during the designated 1-second interval

• get_page_calls_issued

  Number of get_page() calls issued during the designated 1-second interval

• 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 designated 1-second interval

• get_page_reqs_completed

  Number of get_page() calls waiting for I/O or I/O completion that have completed during the designated 1-second interval

• seconds_ago

  Number of 1-second intervals in the past of the interval to which this row applies

Notes

Each row in this table corresponds to an instance of PGMAN during a 1-second interval occurring from 0 to 19 seconds ago; there is one such instance per LDM thread plus an additional instance for each data node.