README.md

pg_stat_ssi_failures

Little extension to account serialization failures in PostgreSQL.

The main purpose of this extension is to provide some counter that can return some kind of perfdata to a monitoring suite.

Functions

• pg_stat_ssi_failures : returns the number of serialization failures that occurred in the cluster.

• pg_stat_ssi_failures_reset : reset the failure counter.

How to monitor this counter ?

In a first step, create an history table to store intermediate values :

CREATE TABLE ssi_failures
    AS SELECT pg_stat_ssi_failures() AS failcount;

This table will store the counter value

Now, you can use the following query, for example with check_pgactivity :

WITH ssifails AS (
  SELECT pg_stat_ssi_failures() AS failcount, failcount AS last_call_failcount FROM ssi_failures
),
update_counter AS (
  UPDATE ssi_failures
     SET failcount = ssifails.failcount
    FROM ssifails
)
SELECT 0 AS dumb_status,
       failcount - last_failcount AS failures
  FROM ssifails;