host_summary_by_statement_latency and x$host_summary_by_statement_latency Sys Schema Views

These views summarize statement statistics grouped by host, sorted by total latency, helping to identify hosts running the most time-consuming queries.

Sys Schema views are available from MariaDB 10.6.

Description

The host_summary_by_statement_latency and x$host_summary_by_statement_latency views summarize statement statistics, grouped by host. Rows are sorted by descending total latency by default. The host_summary_by_statement_latency view is intended to be easier for human reading, while the x$host_summary_by_statement_latency view provides the data in raw form, intended for tools that process the data.

They contain the following columns:

Column	Description
host	Host that the client connected from, or background for background threads (where the HOST column in the underlying Performance Schema table is NULL).
total	Total number of statements for the host.
max_latency	Maximum single wait time of timed statements for the host.
lock_latency	Total time spent by timed statements for the host waiting for locks.
total_latency	Total wait time of timed statements for the host.
rows_sent	Total number of rows returned by statements for the host.
rows_examined	Total number of rows read from storage engines by statements for the host.
rows_affected	Total number of rows affected by statements for the host.
full_scans	Total number of full table scans by statements for the host.

Example

SELECT * FROM sys.host_summary_by_statement_latency\G
*************************** 1. row ***************************
         host: localhost
        total: 1042
total_latency: 816.89 ms
  max_latency: 64.51 ms
 lock_latency: 215.64 ms
    rows_sent: 750599937895985
rows_examined: 13548
rows_affected: 6
   full_scans: 33
*************************** 2. row ***************************
         host: background
        total: 0
total_latency: 0 ps
  max_latency: 0 ps
 lock_latency: 0 ps
    rows_sent: 0
rows_examined: 0
rows_affected: 0
   full_scans: 0

SELECT * FROM sys.x$host_summary_by_statement_latency\G
*************************** 1. row ***************************
         host: localhost
        total: 1041
total_latency: 812132706000
  max_latency: 64507216000
 lock_latency: 215301000000
    rows_sent: 750599937895983
rows_examined: 13110
rows_affected: 6
   full_scans: 32
*************************** 2. row ***************************
         host: background
        total: 0
total_latency: 0
  max_latency: 0
 lock_latency: 0
    rows_sent: 0
rows_examined: 0
rows_affected: 0
   full_scans: 0

_{This page is licensed: CC BY-SA / Gnu FDL}