Обсуждение: relationship of backend_start, query_start, state_change

Hello,

I'm looking at my pg_stat_activity and trying to figure out what is causing some of these processes.  I'm using this query:

SELECT pid, wait_event, state_change, backend_start, xact_start, query_start, state_change - query_start, query from pg_stat_activity where datname= 'my_database' and state in ('idle', 'idle in transaction', 'idle in transaction (aborted)', 'disabled');

and what I see is the same PID which have been around for a while in the same query (COMMIT), but the query_start and state_change are updated and close to each other:

  pid  | wait_event |         state_change          |         backend_start         | xact_start |          query_start          |    ?column?     | query  

-------+------------+-------------------------------+-------------------------------+------------+-------------------------------+-----------------+--------

 32506 | ClientRead | 2020-04-23 09:29:05.6793-07   | 2020-04-23 01:00:19.612478-07 |            | 2020-04-23 09:29:05.679275-07 | 00:00:00.000025 | COMMIT

 32506 | ClientRead | 2020-04-23 09:30:33.247119-07 | 2020-04-23 01:00:19.612478-07 |                               | 2020-04-23 09:30:33.247109-07 | 00:00:00.00001  | COMMIT

 32506 | ClientRead | 2020-04-23 09:31:31.506914-07 | 2020-04-23 01:00:19.612478-07 |                               | 2020-04-23 09:31:31.506905-07 | 00:00:00.000009 | COMMIT

 32506 | ClientRead | 2020-04-23 09:32:32.06656-07  | 2020-04-23 01:00:19.612478-07 |            | 2020-04-23 09:32:32.066552-07 | 00:00:00.000008 | COMMIT

 32506 | ClientRead | 2020-04-23 09:36:51.579939-07 | 2020-04-23 01:00:19.612478-07 |            | 2020-04-23 09:36:51.579931-07 | 00:00:00.000008 | COMMIT

So can we close this thread because it's been around since 1 AM and the last query is always "COMMIT"?  Or should we keep it open because the query_start keeps updating, and the state_change is basically keeping up with query_start?

-----
Si Chen
Open Source Strategies, Inc.

Our Mission: https://www.youtube.com/watch?v=Uc7lmvnuJHY

Hello,

I'm looking at my pg_stat_activity and trying to figure out what is causing some of these processes.  I'm using this query:

SELECT pid, wait_event, state_change, backend_start, xact_start, query_start, state_change - query_start, query from pg_stat_activity where datname= 'my_database' and state in ('idle', 'idle in transaction', 'idle in transaction (aborted)', 'disabled');

On Thu, Apr 23, 2020 at 9:37 AM Si Chen <sichen@opensourcestrategies.com> wrote:

Hello,

I'm looking at my pg_stat_activity and trying to figure out what is causing some of these processes.  I'm using this query:

SELECT pid, wait_event, state_change, backend_start, xact_start, query_start, state_change - query_start, query from pg_stat_activity where datname= 'my_database' and state in ('idle', 'idle in transaction', 'idle in transaction (aborted)', 'disabled');

Including the "state" field should clear things up considerably.

https://www.postgresql.org/docs/current/monitoring-stats.html#PG-STAT-ACTIVITY-VIEW 

 

David J.

On Thu, Apr 23, 2020 at 9:37 AM Si Chen <sichen@opensourcestrategies.com> wrote:

Hello,

I'm looking at my pg_stat_activity and trying to figure out what is causing some of these processes.  I'm using this query:

SELECT pid, wait_event, state_change, backend_start, xact_start, query_start, state_change - query_start, query from pg_stat_activity where datname= 'my_database' and state in ('idle', 'idle in transaction', 'idle in transaction (aborted)', 'disabled');

Including the "state" field should clear things up considerably.

https://www.postgresql.org/docs/current/monitoring-stats.html#PG-STAT-ACTIVITY-VIEW 

 

Hi David,

On Thu, Apr 23, 2020 at 6:55 PM David G. Johnston <david.g.johnston@gmail.com> wrote:

On Thu, Apr 23, 2020 at 9:37 AM Si Chen <sichen@opensourcestrategies.com> wrote:

Hello,

I'm looking at my pg_stat_activity and trying to figure out what is causing some of these processes.  I'm using this query:

SELECT pid, wait_event, state_change, backend_start, xact_start, query_start, state_change - query_start, query from pg_stat_activity where datname= 'my_database' and state in ('idle', 'idle in transaction', 'idle in transaction (aborted)', 'disabled');

Including the "state" field should clear things up considerably.

https://www.postgresql.org/docs/current/monitoring-stats.html#PG-STAT-ACTIVITY-VIEW 

The transactions are idle, they are filtered in the WHERE statement.