Thread: possibly outdated info in pg_stat_activity

possibly outdated info in pg_stat_activity

From
Rajesh Kumar Mallah
Date:
Hi,

PID 3533 does not exists in the system but its still  in pg_stat_activity.
This is PostgreSQL 8.0.3 on i686-pc-linux-gnu, compiled by GCC gcc
(GCC) 3.2.3 20030502 (Red Hat Linux 3.2.3-49). Not sure if its already
known issue , advance apologies if
so.

tradein_clients=# SELECT procpid,query_start,
substring(btrim(current_query),0,50)  from pg_stat_activity order by
query_start limit 20;
+---------+----------------------------------+---------------------------------------------------+
| procpid |           query_start            |
substring                     |
+---------+----------------------------------+---------------------------------------------------+
|    3533 | 2005-10-16 22:26:21.981728+05:30 | select
prod_serv,memb_affil,eyp,pacode,estd,entry |
|    3649 | 2005-10-16 22:26:33.168702+05:30 | <IDLE> in transaction
                          |
|   31579 | 2005-10-17 10:19:21.185764+05:30 | <IDLE>
                          |
|   32142 | 2005-10-17 10:21:46.696032+05:30 | <IDLE>
                          |
|   31715 | 2005-10-17 10:21:57.676293+05:30 | <IDLE>
                          |
|    3508 | 2005-10-17 10:22:12.500686+05:30 | <IDLE>
                          |
|     830 | 2005-10-17 10:23:04.34449+05:30  | <IDLE>
                          |
|   32197 | 2005-10-17 10:23:05.458473+05:30 | <IDLE>
                          |
|   31210 | 2005-10-17 10:23:20.55451+05:30  | <IDLE>
                          |
|     751 | 2005-10-17 10:24:33.519166+05:30 | <IDLE>
                          |
|   31908 | 2005-10-17 10:24:51.839088+05:30 | <IDLE>
                          |
|   31651 | 2005-10-17 10:24:53.896042+05:30 | <IDLE>
                          |
|    8777 | 2005-10-17 10:24:54.074668+05:30 | <IDLE>
                          |
|   31338 | 2005-10-17 10:25:28.248292+05:30 | <IDLE>
                          |
|    7547 | 2005-10-17 10:25:36.473533+05:30 | <IDLE>
                          |
|   10387 | 2005-10-17 10:26:00.250297+05:30 | <IDLE>
                          |
|    1399 | 2005-10-17 10:26:02.775205+05:30 | <IDLE>
                          |
|     867 | 2005-10-17 10:26:13.393084+05:30 | <IDLE>
                          |
|   10543 | 2005-10-17 10:26:14.258694+05:30 | <IDLE>
                          |
|    8680 | 2005-10-17 10:26:19.020959+05:30 | <IDLE>
                          |
+---------+----------------------------------+---------------------------------------------------+
(20 rows)

Re: possibly outdated info in pg_stat_activity

From
Alvaro Herrera
Date:
Rajesh Kumar Mallah wrote:

> PID 3533 does not exists in the system but its still  in pg_stat_activity.
> This is PostgreSQL 8.0.3 on i686-pc-linux-gnu, compiled by GCC gcc
> (GCC) 3.2.3 20030502 (Red Hat Linux 3.2.3-49).

This is normal behavior.  Sometimes the packets used to update the stat
collector's information are lost due to the nature of the UDP socket.
You shouldn't see this problem under light load.

--
Alvaro Herrera                         Architect, http://www.EnterpriseDB.com
"The first of April is the day we remember what we are
the other 364 days of the year"  (Mark Twain)