[pgpool-general: 7222] Re: Idle connection in database

Tatsuo Ishii ishii at sraoss.co.jp
Sun Aug 30 16:41:08 JST 2020


Ok, I have tried with your test data and pgpool settings. Also I added
log_disconnections to postgresql.conf so that when Pgpool-II
disconnects backend.  However I was not able to reproduce your
problem. Pgpool-II worked as expected (10 seconds after the test
script ends, connection was terminated on all backends).

What version of Pgpool-II are you using?

> Hi Tatsuo,
> 
> 
> No, because my primary has node ID 0 and standby has node ID 1.
> 
> Patch will help if my primary node ID is not 0 rite?
> 
> Thanks and Regards,
> Nikhil
> 
> 
> On Sun, Aug 30, 2020, 12:19 Tatsuo Ishii <ishii at sraoss.co.jp> wrote:
> 
>> Before these tests, have applied the patch?
>>
>> > Hi Tatsuo,
>> >
>> >
>> > I have to reopen this issue because after a lot of debugging and reading
>> > documentation on connection_life_time though there is not much of it,
>> this
>> > parameter doesn't work as it should.
>> >
>> > First I want to be correct in my understanding that this parameter
>> > terminates cached backend connections in the database.So, I test a simple
>> > scenario as follows:
>> >
>> > PGPOOL -  128.199.224.132
>> >
>> > *Parameters set for pooling*
>> > serialize_accept=on
>> > child_life_time=0
>> > child_max_connections=0
>> > client_idle_limit=0
>> > connection_life_time=10
>> >
>> > *I am running a mixed.sql file which contain below statements*
>> > BEGIN;
>> > SELECT CURRENT_TIMESTAMP;
>> > INSERT  into t1 values(3);
>> > INSERT  into t1 values(4);
>> > select pg_sleep(5);
>> > INSERT  into t1 values(5);
>> > UPDATE t1 set id=4 where id=5;
>> > END;
>> >
>> > After executing some inserts it will sleep for 5 seconds and then execute
>> > one update and an insert before closing the connection.
>> >
>> >
>> > *1) Status of nodes*
>> > -bash-4.2$ psql -h 128.199.224.132 -p 9999 -U enterprisedb
>> > psql.bin (11.6.13)
>> > Type "help" for help.
>> >
>> > edb=# show pool_nodes;
>> >  node_id |    hostname     | port | status | lb_weight |  role   |
>> > select_cnt | load_balance_node | replication_delay | replication_state |
>> > replication_syn
>> > c_state | last_status_change
>> >
>> ---------+-----------------+------+--------+-----------+---------+------------+-------------------+-------------------+-------------------+----------------
>> > --------+---------------------
>> >  0       | 128.199.222.92  | 5445 | up     | 0.000000  | primary | 0
>> >    | false             | 0                 |                   |
>> >         | 2020-08-30 04:58:24
>> >  1       | 128.199.222.124 | 5445 | up     | 1.000000  | standby | 0
>> >    | true              | 0                 |                   |
>> >         | 2020-08-30 04:58:24
>> > (2 rows)
>> >
>> > *2) Running the mixed.sql file*
>> > -bash-4.2$ psql -h 128.199.224.132 -p 9999 -U enterprisedb -f mixed.sql
>> > BEGIN
>> >         current_timestamp
>> > ----------------------------------
>> >  30-AUG-20 10:31:47.396527 +05:30
>> > (1 row)
>> >
>> > INSERT 0 1
>> > INSERT 0 1
>> >  pg_sleep
>> > ----------
>> >
>> > (1 row)
>> >
>> > INSERT 0 1
>> > UPDATE 1
>> > COMMIT
>> > -bash-4.2$
>> >
>> > *3) pool_pools output shows pgpool (pid - 31560) created one connection
>> to
>> > master(pid - 31550) and one to standby (pid - 28954) *
>> >
>> > edb=# show pool_pools;
>> >  pool_pid |     start_time      | pool_id | backend_id | database |
>> > username   |     create_time     | majorversion | minorversion |
>> > pool_counter | pool_
>> > backendpid | pool_connected
>> >
>> ----------+---------------------+---------+------------+----------+--------------+---------------------+--------------+--------------+--------------+------
>> > -----------+----------------
>> >  31560    | 2020-08-30 04:51:54 | 0       | 0          | edb      |
>> > enterprisedb | 2020-08-30 05:01:47 | 3            | 0            | 1
>> >      | 31550
>> >            | 0
>> >  31560    | 2020-08-30 04:51:54 | 0       | 1          | edb      |
>> > enterprisedb | 2020-08-30 05:01:47 | 3            | 0            | 1
>> >      | 28954
>> >            | 0
>> >
>> > *4) Status of process id 31550 on master.After the run, as seen below on
>> > the database is idle*
>> >
>> > -bash-4.2$ ps -ef |grep 224.132
>> > enterpr+ 31550  9148  0 05:01 ?        00:00:00 postgres: enterprisedb
>> edb
>> > 128.199.224.132[49656] idle
>> >
>> > *5) Status of processid 31560 on pgpool.* *After the run, as seen below
>> > pgpool has released connection as soon as transaction completes*
>> > [root at pgpool-p pgpool4.1]# ps -ef |grep 31560
>> > enterpr+ 31560 31557  0 04:51 ?        00:00:00 pgpool: wait for accept
>> lock
>> >
>> >
>> > *6) After 10 seconds, this cached connection on database should have been
>> > terminated as per my understanding of connection_life_time parameter but
>> as
>> > seen below it has not terminated*
>> > edb=# select * from pg_stat_activity where client_addr
>> ='128.199.224.132';
>> > -[ RECORD 1 ]----+---------------------------------
>> > datid            | 67127
>> > datname          | edb
>> > pid              | 31550
>> > usesysid         | 10
>> > usename          | enterprisedb
>> > application_name | psql.bin
>> > client_addr      | 128.199.224.132
>> > client_hostname  |
>> > client_port      | 49656
>> > backend_start    | 30-AUG-20 10:31:47.380345 +05:30
>> > xact_start       |
>> > query_start      | 30-AUG-20 10:31:52.411607 +05:30
>> > state_change     | 30-AUG-20 10:31:52.411714 +05:30
>> > wait_event_type  | Client
>> > wait_event       | ClientRead
>> > state            | idle
>> > backend_xid      |
>> > backend_xmin     |
>> > query            |  DISCARD ALL
>> > backend_type     | client backend
>> >
>> > Do not mind the timestamp, it is in IST for the above query.
>> >
>> > *7) From the pgpool logs, it sets the alarm after 10 sec but doesn't
>> really
>> > close the connection after 10 seconds*
>> > Aug 30 05:01:52 Pgpool-p pgpool[*31560*]: [252-2] 2020-08-30 05:01:52:
>> pid
>> > 31560: DETAIL:  setting alarm after 10 seconds
>> >
>> > Attaching pgpool logs as well.
>> >
>> >
>> > On Wed, Aug 12, 2020 at 9:02 PM Nikhil Shetty <nikhil.dba04 at gmail.com>
>> > wrote:
>> >
>> >> Hi Tatsuo,
>> >>
>> >> Thank you, I will check how this works.
>> >>
>> >>
>> >> On Tue, Aug 11, 2020 at 5:52 PM Tatsuo Ishii <ishii at sraoss.co.jp>
>> wrote:
>> >>
>> >>> Hi Nikhil,
>> >>>
>> >>> > Hi Tatsuo,
>> >>> >
>> >>> > We are checking the patch internally before we go ahead and deploy in
>> >>> > production.
>> >>>
>> >>> Ok.
>> >>>
>> >>> > If I want to set only one of either connection_life_time or
>> >>> > client_idle_limit. What do you recommend? Should I set
>> >>> > client_idle_limit=120 and  connection_life_time=0, do you foresee any
>> >>> > effects of these settings for connection pooling?
>> >>>
>> >>> In general connection_life_time is better because:
>> >>>
>> >>> 1. when client_idle_limit expires, pgpool needs to fork a new process,
>> >>>    but connection_life_time does not.
>> >>>
>> >>> 2. when client_idle_limit expires, it looses mutiple connection pools
>> >>>    (this only applicatable fro max_pool > 1 case) because the
>> >>>    connection pools the process hold go away.
>> >>>
>> >>> However if you have very short and frequent sessions, more alarm
>> >>> system calls with connection_life_time are required and maybe
>> >>> client_idle_limit wins in this case.
>> >>>
>> >>> > Thank you for your time and support.
>> >>> >
>> >>> > Thanks and Regards,
>> >>> > Nikhil
>> >>> >
>> >>> > On Mon, Aug 10, 2020 at 11:58 AM Tatsuo Ishii <ishii at sraoss.co.jp>
>> >>> wrote:
>> >>> >
>> >>> >> Hi Nikhil,
>> >>> >>
>> >>> >> I have been investigating if there's any case when
>> >>> >> connection_life_time is not working. Actually it *is*. If primary
>> node
>> >>> >> is not node 0, connection_life_time does not work. Attached is the
>> >>> >> patch to fix that.  Please try, if you like.
>> >>> >>
>> >>> >> > According to your previous message, corresponding pgpool process
>> was
>> >>> >> > not there, but PostgreSQL backend process were still running. I
>> >>> >> > suspect the backend process was waiting for TCP/IP connection was
>> >>> >> > terminated. But to know what was actually happening, I was waiting
>> >>> for
>> >>> >> > your response.
>> >>> >> >
>> >>> >> >>> "DISCARD ALL" and state idle. I will have to test again to check
>> >>> the
>> >>> >> socket
>> >>> >> >>> status of pid.I will get back on this
>> >>> >> >
>> >>> >> > What was that?
>> >>> >> >
>> >>> >> >> Hi Tatsuo,
>> >>> >> >>
>> >>> >> >>
>> >>> >> >> Ant reason why connection_idle_limit doesn't remove backend
>> >>> connection
>> >>> >> >> after time limit is crossed
>> >>> >> >>
>> >>> >> >> Thanks and Regards,
>> >>> >> >> Nikhil
>> >>> >> >>
>> >>> >> >> On Sun, Aug 2, 2020, 12:48 Nikhil Shetty <nikhil.dba04 at gmail.com
>> >
>> >>> >> wrote:
>> >>> >> >>
>> >>> >> >>> Hi Tatsuo,
>> >>> >> >>>
>> >>> >> >>> I want to correct my statement from previous email:
>> >>> >> >>>
>> >>> >> >>> From ps status *I could not see *that the process (18190 and
>> 18193)
>> >>> >> were
>> >>> >> >>> still present on pgpool but the backend process was still
>> present
>> >>> with
>> >>> >> >>> "DISCARD ALL" and state idle. I will have to test again to check
>> >>> the
>> >>> >> socket
>> >>> >> >>> status of pid.I will get back on this
>> >>> >> >>>
>> >>> >> >>> On Sun, Aug 2, 2020 at 12:15 PM Nikhil Shetty <
>> >>> nikhil.dba04 at gmail.com>
>> >>> >> >>> wrote:
>> >>> >> >>>
>> >>> >> >>>> Hi Tatsuo,
>> >>> >> >>>>
>> >>> >> >>>> >> Assuming you executed "show pool_pools" long after
>> 2020-08-01
>> >>> >> >>>> >> 06:21:26, that is very strange because connection_life_time
>> >>> should
>> >>> >> >>>> >> have been already expired. I wonder if pgpool tried to
>> >>> disconnect
>> >>> >> the
>> >>> >> >>>> >> connection but failed. To check what actually happend, can
>> you
>> >>> >> check
>> >>> >> >>>> >> ps status of pgpool process 18190 and 18193?
>> >>> >> >>>>
>> >>> >> >>>> >> Also it would be nice you can examine the socket status of
>> >>> >> PostgreSQL
>> >>> >> >>>> >> backend 29321 and 29619, and pgpool socket status of process
>> >>> 18190
>> >>> >> and
>> >>> >> >>>> >> 18193?
>> >>> >> >>>>
>> >>> >> >>>> From ps status I could see that the process (18190 and 18193)
>> were
>> >>> >> still
>> >>> >> >>>> present on pgpool. I will have to test again to check the
>> socket
>> >>> >> status of
>> >>> >> >>>> pid.I will get back on this
>> >>> >> >>>>
>> >>> >> >>>> Meanwhile, I did some testing of my own for these two
>> parameters(
>> >>> >> >>>> client_idle_limit and connection_life_time ) and their
>> behaviour:
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >> >>>> *Test:*
>> >>> >> >>>>
>> >>> >> >>>> Database IP:128.199.222.92(master)
>> >>> >> >>>> Pgpool IP: 128.199.224.132
>> >>> >> >>>>
>> >>> >> >>>> *Scenario1:*
>> >>> >> >>>>
>> >>> >> >>>> max_pool=1
>> >>> >> >>>> num_init_children=100
>> >>> >> >>>> serialize_accept=on
>> >>> >> >>>> child_max_connections=0
>> >>> >> >>>> child_life_time=0
>> >>> >> >>>> connection_life_time=60
>> >>> >> >>>> client_idle_limit=0
>> >>> >> >>>>
>> >>> >> >>>> *1. Connected to Pgpool and ran a query with \watch 1:*
>> >>> >> >>>> select count(*) from pgbench_accounts ;
>> >>> >> >>>> \watch 1
>> >>> >> >>>> Sat 01 Aug 2020 07:25:54 AM UTC (every 1s)
>> >>> >> >>>>
>> >>> >> >>>>   count
>> >>> >> >>>> ---------
>> >>> >> >>>>  6000000
>> >>> >> >>>>
>> >>> >> >>>> *2. Checking session in database, one session is active from
>> >>> pgpool*
>> >>> >> >>>>                             Sat 01 Aug 2020 07:26:14 AM UTC
>> >>> (every 1s)
>> >>> >> >>>>
>> >>> >> >>>>  pid  |                  query                  |   usename
>> |
>> >>> >> >>>> client_addr   | count | state
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >>
>> >>>
>> ------+-----------------------------------------+--------------+-----------------+-------+--------
>> >>> >> >>>>  3420 | select count(*) from pgbench_accounts ; | enterprisedb
>> |
>> >>> >> >>>> 128.199.224.132 |     1 | active
>> >>> >> >>>> (1 row)
>> >>> >> >>>>
>> >>> >> >>>> *3. Stopped the query after sometime using Ctrl-C but session
>> is
>> >>> still
>> >>> >> >>>> open*
>> >>> >> >>>> Sat 01 Aug 2020 07:27:35 AM UTC (every 1s)
>> >>> >> >>>>
>> >>> >> >>>>   count
>> >>> >> >>>> ---------
>> >>> >> >>>>  6000000
>> >>> >> >>>> (1 row)
>> >>> >> >>>>
>> >>> >> >>>> ^Cedb=#
>> >>> >> >>>> edb=#
>> >>> >> >>>>
>> >>> >> >>>> *4. Checking session in database, state is now idle*
>> >>> >> >>>>
>> >>> >> >>>>                            Sat 01 Aug 2020 07:28:14 AM UTC
>> (every
>> >>> 1s)
>> >>> >> >>>>
>> >>> >> >>>>  pid  |                  query                  |   usename
>> |
>> >>> >> >>>> client_addr   | count | state
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >>
>> >>>
>> ------+-----------------------------------------+--------------+-----------------+-------+-------
>> >>> >> >>>>  3420 | select count(*) from pgbench_accounts ; | enterprisedb
>> |
>> >>> >> >>>> 128.199.224.132 |     1 | idle
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >> >>>> *5. Checking session in database after 2 minutes, I can still
>> see
>> >>> the
>> >>> >> >>>> database session idle*
>> >>> >> >>>>
>> >>> >> >>>>                            Sat 01 Aug 2020 07:30:02 AM UTC
>> (every
>> >>> 1s)
>> >>> >> >>>>
>> >>> >> >>>>  pid  |                  query                  |   usename
>> |
>> >>> >> >>>> client_addr   | count | state
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >>
>> >>>
>> ------+-----------------------------------------+--------------+-----------------+-------+-------
>> >>> >> >>>>  3420 | select count(*) from pgbench_accounts ; | enterprisedb
>> |
>> >>> >> >>>> 128.199.224.132 |     1 | idle
>> >>> >> >>>>
>> >>> >> >>>> *6. Checking connection on pgpool server. connection is still
>> open
>> >>> >> from
>> >>> >> >>>> pgpool to database*
>> >>> >> >>>>
>> >>> >> >>>> ps -ef|grep edb
>> >>> >> >>>> enterpr+ 24170 24162  0 06:51 ?        00:00:00 pgpool:
>> >>> enterprisedb
>> >>> >> edb
>> >>> >> >>>> 128.199.222.92(34402) idle
>> >>> >> >>>>
>> >>> >> >>>> *7. After being idle for more than 60 seconds, connections are
>> >>> still
>> >>> >> open
>> >>> >> >>>> from pgpool and on database.Connection is removed from pgpool
>> >>> server
>> >>> >> after
>> >>> >> >>>> I quit from the psql terminal but still present in the
>> database as
>> >>> >> show
>> >>> >> >>>> below:*
>> >>> >> >>>>               Sat 01 Aug 2020 07:34:26 AM UTC (every 1s)
>> >>> >> >>>>
>> >>> >> >>>>  pid  |    query     |   usename    |   client_addr   | count |
>> >>> state
>> >>> >> >>>>
>> >>> ------+--------------+--------------+-----------------+-------+-------
>> >>> >> >>>>  3420 |  DISCARD ALL | enterprisedb | 128.199.224.132 |     1 |
>> >>> idle
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >> >>>> *Scenario2:*
>> >>> >> >>>>
>> >>> >> >>>> max_pool=1
>> >>> >> >>>> num_init_children=100
>> >>> >> >>>> serialize_accept=on
>> >>> >> >>>> child_max_connections=0
>> >>> >> >>>> child_life_time=0
>> >>> >> >>>> connection_life_time=0
>> >>> >> >>>> client_idle_limit=60
>> >>> >> >>>>
>> >>> >> >>>> *1. Connected to Pgpool and ran a query with \watch 1:*
>> >>> >> >>>> edb=# \! date
>> >>> >> >>>> Sat Aug  1 07:38:45 UTC 2020
>> >>> >> >>>> select count(*) from pgbench_accounts ;
>> >>> >> >>>> \watch 1
>> >>> >> >>>> edb=# select count(*) from pgbench_accounts ;
>> >>> >> >>>>   count
>> >>> >> >>>> ---------
>> >>> >> >>>>  6000000
>> >>> >> >>>> (1 row)
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >> >>>> *2. Checking session in database, one session is active from
>> >>> pgpool*
>> >>> >> >>>>
>> >>> >> >>>>                             Sat 01 Aug 2020 07:39:55 AM UTC
>> >>> (every 1s)
>> >>> >> >>>>
>> >>> >> >>>>   pid  |                  query                  |   usename
>>   |
>> >>> >> >>>> client_addr   | count | state
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >>
>> >>>
>> -------+-----------------------------------------+--------------+-----------------+-------+--------
>> >>> >> >>>>  13427 | select count(*) from pgbench_accounts ; |
>> enterprisedb |
>> >>> >> >>>> 128.199.224.132 |     1 | active
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >> >>>> *3. Stopped the query after sometime using Ctrl-C but session
>> is
>> >>> still
>> >>> >> >>>> open*
>> >>> >> >>>> Sat 01 Aug 2020 07:41:39 AM UTC (every 1s)
>> >>> >> >>>>
>> >>> >> >>>>   count
>> >>> >> >>>> ---------
>> >>> >> >>>>  6000000
>> >>> >> >>>> ^Cedb=#
>> >>> >> >>>> edb=#
>> >>> >> >>>>
>> >>> >> >>>> *4. Checking session in database, state is now idle*
>> >>> >> >>>>
>> >>> >> >>>>                             Sat 01 Aug 2020 07:42:12 AM UTC
>> >>> (every 1s)
>> >>> >> >>>>
>> >>> >> >>>>   pid  |                  query                  |   usename
>>   |
>> >>> >> >>>> client_addr   | count | state
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >>
>> >>>
>> -------+-----------------------------------------+--------------+-----------------+-------+-------
>> >>> >> >>>>  13427 | select count(*) from pgbench_accounts ; |
>> enterprisedb |
>> >>> >> >>>> 128.199.224.132 |     1 | idle
>> >>> >> >>>> (1 row)
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >> >>>> *5. Checking session in database after 2 minutes, there is no
>> >>> session
>> >>> >> in
>> >>> >> >>>> the database.*
>> >>> >> >>>>
>> >>> >> >>>>   Sat 01 Aug 2020 07:42:42 AM UTC (every 1s)
>> >>> >> >>>>
>> >>> >> >>>>  pid | query | usename | client_addr | count | state
>> >>> >> >>>> -----+-------+---------+-------------+-------+-------
>> >>> >> >>>> (0 rows)
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >> >>>> *6. Checking connection on pgpool server. No connection open in
>> >>> >> pgpool to
>> >>> >> >>>> database*
>> >>> >> >>>> ps -ef|grep edb
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >> >>>> *Observations:*
>> >>> >> >>>>
>> >>> >> >>>> With client_idle_limit of 60 seconds, all connections are
>> closed
>> >>> after
>> >>> >> >>>> being idle for more than 1 minute. I can see psql session in
>> >>> database
>> >>> >> is
>> >>> >> >>>> still present as shown below, because
>> >>> >> >>>> I did not quit from psql terminal yet:
>> >>> >> >>>>
>> >>> >> >>>> [root at master ~]# ps -ef |grep 128.199.224.132
>> >>> >> >>>> enterpr+ 13193 28563  0 07:38 pts/0    00:00:00 /bin/bash
>> >>> /bin/psql -p
>> >>> >> >>>> 9999 -h 128.199.224.132
>> >>> >> >>>> enterpr+ 13198 13193  0 07:38 pts/0    00:00:00 /bin/psql.bin
>> -p
>> >>> 9999
>> >>> >> -h
>> >>> >> >>>> 128.199.224.132
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >> >>>> From scenario 2( client_idle_limit = 60), we can say that when
>> >>> >> >>>> client_idle_limit is triggered client is disconnected, no
>> database
>> >>> >> >>>> connection is in use but the session still remains on
>> server.If i
>> >>> >> start
>> >>> >> >>>> running query
>> >>> >> >>>> on same psql session, it will first reset connection and then
>> run
>> >>> the
>> >>> >> >>>> query, this will again create a new connection to the database.
>> >>> >> >>>>
>> >>> >> >>>> From scenario 1(connection_life_time = 60), there is no real
>> >>> benefit I
>> >>> >> >>>> see. I assumed the connections(DISCARD ALL) present in database
>> >>> will
>> >>> >> be
>> >>> >> >>>> reused but each time I connected to the database, it created a
>> new
>> >>> >> >>>> connection as seen below:
>> >>> >> >>>>
>> >>> >> >>>>   pid  |    query     |   usename    |   client_addr   | count
>> |
>> >>> state
>> >>> >> >>>>
>> >>> >>
>> -------+--------------+--------------+-----------------+-------+-------
>> >>> >> >>>>  12895 |              | enterprisedb | 128.199.224.132 |     1
>> |
>> >>> idle
>> >>> >> >>>>   3420 |  DISCARD ALL | enterprisedb | 128.199.224.132 |     1
>> |
>> >>> idle
>> >>> >> >>>>  12531 |  DISCARD ALL | enterprisedb | 128.199.224.132 |     1
>> |
>> >>> idle
>> >>> >> >>>>  12636 |  DISCARD ALL | enterprisedb | 128.199.224.132 |     1
>> |
>> >>> idle
>> >>> >> >>>>  12698 |  DISCARD ALL | enterprisedb | 128.199.224.132 |     1
>> |
>> >>> idle
>> >>> >> >>>>  12751 |  DISCARD ALL | enterprisedb | 128.199.224.132 |     1
>> |
>> >>> idle
>> >>> >> >>>>  12773 |  DISCARD ALL | enterprisedb | 128.199.224.132 |     1
>> |
>> >>> idle
>> >>> >> >>>>  12862 |  DISCARD ALL | enterprisedb | 128.199.224.132 |     1
>> |
>> >>> idle
>> >>> >> >>>>  12878 |  DISCARD ALL | enterprisedb | 128.199.224.132 |     1
>> |
>> >>> idle
>> >>> >> >>>> (9 rows)
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >> >>>> Thanks and Regards,
>> >>> >> >>>> Nikhil
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >> >>>>
>> >>> >> >>>> On Sat, Aug 1, 2020 at 6:45 PM Tatsuo Ishii <
>> ishii at sraoss.co.jp>
>> >>> >> wrote:
>> >>> >> >>>>
>> >>> >> >>>>> > Hi,
>> >>> >> >>>>> >
>> >>> >> >>>>> > Yes, we can see the pid
>> >>> >> >>>>> >
>> >>> >> >>>>> > show pool_pools;
>> >>> >> >>>>> > pool_pid |     start_time      | pool_id | backend_id |
>> >>> database |
>> >>> >> >>>>> > username   |     create_time     | majorversion |
>> minorversion
>> >>> |
>> >>> >> >>>>> > pool_counter | pool_backendpid | pool_connected
>> >>> >> >>>>> >
>> >>> >> >>>>> > 18190    | 2020-08-01 06:14:41 | 0       | 1          | edb
>> >>>   |
>> >>> >> >>>>> > enterprisedb | 2020-08-01 06:19:52 | 3            | 0
>> >>>   |
>> >>> >> 1
>> >>> >> >>>>> >      | *29321*          | 0
>> >>> >> >>>>> > 18193    | 2020-08-01 06:14:41 | 0       | 1          | edb
>> >>>   |
>> >>> >> >>>>> > enterprisedb | 2020-08-01 06:21:26 | 3            | 0
>> >>>   |
>> >>> >> 1
>> >>> >> >>>>> >      | *29619          *| 0
>> >>> >> >>>>> >
>> >>> >> >>>>> >
>> >>> >> >>>>> > select pid,query,usename,state from pg_stat_activity where
>> >>> >> >>>>> > client_addr='128.199.224.132' group by usename,query,pid;
>> >>> >> >>>>> >  pid  |    query     |   usename    | state
>> >>> >> >>>>> > -------+--------------+--------------+-------
>> >>> >> >>>>> >  *29321 *|  DISCARD ALL | enterprisedb | idle
>> >>> >> >>>>> >  *29619* |  DISCARD ALL | enterprisedb | idle
>> >>> >> >>>>>
>> >>> >> >>>>> Assuming you executed "show pool_pools" long after 2020-08-01
>> >>> >> >>>>> 06:21:26, that is very strange because connection_life_time
>> >>> should
>> >>> >> >>>>> have been already expired. I wonder if pgpool tried to
>> >>> disconnect the
>> >>> >> >>>>> connection but failed. To check what actually happend, can you
>> >>> check
>> >>> >> >>>>> ps status of pgpool process 18190 and 18193?
>> >>> >> >>>>>
>> >>> >> >>>>> Also it would be nice you can examine the socket status of
>> >>> PostgreSQL
>> >>> >> >>>>> backend 29321 and 29619, and pgpool socket status of process
>> >>> 18190
>> >>> >> and
>> >>> >> >>>>> 18193?
>> >>> >> >>>>>
>> >>> >> >>>>> Best regards,
>> >>> >> >>>>> --
>> >>> >> >>>>> Tatsuo Ishii
>> >>> >> >>>>> SRA OSS, Inc. Japan
>> >>> >> >>>>> English: http://www.sraoss.co.jp/index_en.php
>> >>> >> >>>>> Japanese:http://www.sraoss.co.jp
>> >>> >> >>>>>
>> >>> >> >>>>
>> >>> >> > _______________________________________________
>> >>> >> > pgpool-general mailing list
>> >>> >> > pgpool-general at pgpool.net
>> >>> >> > http://www.pgpool.net/mailman/listinfo/pgpool-general
>> >>> >>
>> >>>
>> >>
>>


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