7a0023688b
When accessing the "host" column, it gives the error in some cases "ERROR: result is out of range". The patch changes the host datatype from int to bigint. |
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| expected | ||
| sql | ||
| .gitignore | ||
| LICENSE | ||
| Makefile | ||
| README.md | ||
| pg_stat_monitor--1.0.sql | ||
| pg_stat_monitor.c | ||
| pg_stat_monitor.conf | ||
| pg_stat_monitor.control | ||
README.md
pg_stat_monitor - Statistics collector for PostgreSQL.
The pg_stat_monitor is statistics collector tool based on PostgreSQL's pg_stat_statement. PostgreSQL’s “pg_stat_statment” provides the basic statistics which is sometimes not enough. The major flaw in this that it accumulates all the queries and its statistics and does not provide aggregate statistics, in that case, the user needs to calculate the aggregate which is quite expensive.
Pg_stat_monitor is build on top of pg_stat_statment, so it provides all the pg_stat_statment plus its own feature set.
Supported PostgreSQL Versions.
Pg_stat_monitor should work on the latest version of PostgreSQL but only tested with these versions of PostgreSQL.
* PostgreSQL Version 11
* PostgreSQL Version 12
* Percona Distribution for PostgreSQL
Installation
There are two ways to install pg_stat_monitor. The first is by downloading the pg_stat_monitor source code and compiling it. The second is to download the deb or rpm packages.
Download and compile
The latest release of pg_stat_monitor can be downloaded from this GitHub page:
https://github.com/Percona-Lab/pg_stat_monitor/releases
or it can be downloaded using the git:
git clone git://github.com/Percona-Lab/pg_stat_monitor.git
After downloading the code, set the path for the PostgreSQL binary:
Compile
cd pg_stat_monitor
make USE_PGXS=1
make USE_PGXS=1 install
Enable Extension
postgres=# alter system set shared_preload_libraries=pg_stat_monitor;
ALTER SYSTEM
sudo systemctl restart postgresql-11
postgres=# create extension pg_stat_monitor;
CREATE EXTENSION
Usage
There are four views, and complete statistics can be accessed using these views.
Pg_stat_monitor Pg_stat_agg_database Pg_stat_agg_user pg_stat_agg_hots
pg_stat_monitor
This is the main view which stores per query-based statistics, similar to pg_stat_statment with some additional columns.
\d pg_stat_monitor;
View "public.pg_stat_monitor"
Column | Type | Collation | Nullable | Default
---------------------+------------------+-----------+----------+---------
userid | oid | | |
dbid | oid | | |
queryid | bigint | | |
query | text | | |
calls | bigint | | |
total_time | double precision | | |
min_time | double precision | | |
max_time | double precision | | |
mean_time | double precision | | |
stddev_time | double precision | | |
rows | bigint | | |
shared_blks_hit | bigint | | |
shared_blks_read | bigint | | |
shared_blks_dirtied | bigint | | |
shared_blks_written | bigint | | |
local_blks_hit | bigint | | |
local_blks_read | bigint | | |
local_blks_dirtied | bigint | | |
local_blks_written | bigint | | |
temp_blks_read | bigint | | |
temp_blks_written | bigint | | |
blk_read_time | double precision | | |
blk_write_time | double precision | | |
host | integer | | |
hist_calls | text | | |
hist_min_time | text | | |
hist_max_time | text | | |
hist_mean_time | text | | |
slow_query | text | | |
cpu_user_time | double precision | | |
cpu_sys_time | double precision | | |
These are new column added to have more detail about the query.
host: Client IP or Hostname
hist_calls: Hourly based 24 hours calls of query histogram
hist_min_time: Hourly based 24 hours min time of query histogram
Hist_max_time: Hourly based 24 hours max time of query histogram
hist_mean_time: Hourly based 24 hours mean time of query histogram
slow_query: Slowest query with actual parameters.
cpu_user_time: CPU user time for that query.
cpu_sys_time: CPU System time for that query.
regression=# \d pg_stat_agg_database
View "public.pg_stat_agg_database"
Column | Type | Collation | Nullable | Default
----------------+--------------------------+-----------+----------+---------
queryid | bigint | | |
dbid | bigint | | |
userid | oid | | |
host | inet | | |
total_calls | integer | | |
min_time | double precision | | |
max_time | double precision | | |
mean_time | double precision | | |
hist_calls | text[] | | |
hist_min_time | text[] | | |
hist_max_time | text[] | | |
hist_mean_time | text[] | | |
first_log_time | timestamp with time zone | | |
last_log_time | timestamp with time zone | | |
cpu_user_time | double precision | | |
cpu_sys_time | double precision | | |
query | text | | |
slow_query | text | | |
# \d pg_stat_agg_user
View "public.pg_stat_agg_user"
Column | Type | Collation | Nullable | Default
----------------+--------------------------+-----------+----------+---------
queryid | bigint | | |
dbid | bigint | | |
userid | oid | | |
host | inet | | |
total_calls | integer | | |
min_time | double precision | | |
max_time | double precision | | |
mean_time | double precision | | |
hist_calls | text[] | | |
hist_min_time | text[] | | |
hist_max_time | text[] | | |
hist_mean_time | text[] | | |
first_log_time | timestamp with time zone | | |
last_log_time | timestamp with time zone | | |
cpu_user_time | double precision | | |
cpu_sys_time | double precision | | |
query | text | | |
slow_query | text | | |
# \d pg_stat_agg_host
View "public.pg_stat_agg_host"
Column | Type | Collation | Nullable | Default
----------------+--------------------------+-----------+----------+---------
queryid | bigint | | |
dbid | bigint | | |
userid | oid | | |
host | inet | | |
total_calls | integer | | |
min_time | double precision | | |
max_time | double precision | | |
mean_time | double precision | | |
hist_calls | text[] | | |
hist_min_time | text[] | | |
hist_max_time | text[] | | |
hist_mean_time | text[] | | |
first_log_time | timestamp with time zone | | |
last_log_time | timestamp with time zone | | |
cpu_user_time | double precision | | |
cpu_sys_time | double precision | | |
query | text | | |
slow_query | text | | |
Examples 1 - In this query we are getting the exact value of f1 which is '05:06:07-07' in the case of slow queries.
# select userid, queryid, query, slow_query, max_time, total_calls from pg_stat_agg_user;
-[ RECORD 1 ]----------------------------------------------------------------------------------------
userid | 10
queryid | -203926152419851453
query | SELECT f1 FROM TIMETZ_TBL WHERE f1 < $1
slow_query | SELECT f1 FROM TIMETZ_TBL WHERE f1 < '05:06:07-07';
max_time | 1.237875
total_calls | 8
2 - Collect all statistics based on the user.
# select usename, query, max_time, total_calls from pg_stat_agg_user au, pg_user u where au.userid = u.usesysid;
usename | query | max_time | total_calls
---------+---------------------------------------------------------+----------+-------------
vagrant | select userid, query, total_calls from pg_stat_agg_user | 0.268842 | 7
foo | select userid, query, total_calls from pg_stat_agg_user | 0.208551 | 1
vagrant | select * from pg_stat_monitor_reset() | 0.0941 | 1
(3 rows)
Limitation
There are some limitations and Todos.
Licence
Copyright (c) 2006 - 2019, Percona LLC.
See LICENSE for full details.