[pgpool-general: 7245] Re: Idle connection in database
Tatsuo Ishii
ishii at sraoss.co.jp
Tue Sep 1 13:52:31 JST 2020
> Hi Tatsuo,
>
> Thanks for the patch.Can I test this patch for both 4.0 and 4.1 versions of
> Pgpool?
No. Please grab patches from git repository.
4.0:
https://git.postgresql.org/gitweb/?p=pgpool2.git;a=patch;h=8ffd26b5333839d42b57bb5c4353547bad8cb39a
4.1:
https://git.postgresql.org/gitweb/?p=pgpool2.git;a=patch;h=5bacc82b0c02582b5da6985c55ef543f51268a69
> Thanks and Regards,
> Nikhil
>
> On Mon, Aug 31, 2020 at 7:02 AM Tatsuo Ishii <ishii at sraoss.co.jp> wrote:
>
>> Ok, attached is a new version of patch. I confirmed that performance
>> was not changed.
>>
>> > Wait. It appears that the patch has a drawback: serious performance
>> > degradation.
>> >
>> > pgbench -c 10 -n -p 11000 -C -t 10 test
>> >
>> > With connection_life_time = 10
>> > tps = 3.316286 (including connections establishing)
>> > tps = 3.680803 (excluding connections establishing)
>> >
>> > Without connection_life_time = 10
>> > tps = 269.660238 (including connections establishing)
>> > tps = 280.479690 (excluding connections establishing)
>> >
>> > Let me think if I coould enhance this...
>> >
>> >> Hi Nikhil,
>> >>
>> >> Ok, here is a patch to fix the problem.
>> >>
>> >> If serialize_accept is enabled, pgpool process tries to acquire
>> >> semaphore locking so that there's only one process which can issue
>> >> accept(2). Unfortunately if connection_life_time is enabled, an alarm
>> >> is set right before the semaphore locking. So when the alarm fires,
>> >> nothing happens because the process is waiting for semaphore locking.
>> >>
>> >> To fix this, "the alarm has been set" flag is added. If the flag is
>> >> set, keep on checking for connection_life_time (plus margin) seconds
>> >> until the alarm is fired, then expires the connection to backend.
>> >>
>> >> Patch attached.
>> >>
>> >>>> Hi Tatsuo,
>> >>>>
>> >>>> I was thinking on that line initially that may be because of
>> >>>> serialize_accept it is not working but I didn't dwell into it much and
>> >>>> didn't test it.
>> >>>>
>> >>>> Thanks for your input Tatsuo, you have been of immense help to find
>> this
>> >>>> problem.
>> >>>>
>> >>>> Will this fix, when it is done, be included in all 4.0 and 4.1
>> versions?
>> >>>
>> >>> Not sure if there's actually a fix, but if there were a fix for this,
>> >>> it will be definitely included in 4.0 and 4.1 branches.
>> >>>
>> >>>> On Sun, Aug 30, 2020, 14:08 Tatsuo Ishii <ishii at sraoss.co.jp> wrote:
>> >>>>
>> >>>>> Ok, I found that if following is set:
>> >>>>>
>> >>>>> serialize_accept=on
>> >>>>>
>> >>>>> then, connection_life_time does not work. (The alarm is not
>> >>>>> fired). Don't know why but I am going to fix this.
>> >>>>>
>> >>>>> > Hi Tatsuo,
>> >>>>> >
>> >>>>> > I am using Pgpool v4.1.1.
>> >>>>> >
>> >>>>> > I have seen similiar behaviour in v4.0.9 as well.
>> >>>>> >
>> >>>>> > Thanks and Regards,
>> >>>>> > Nikhil
>> >>>>> >
>> >>>>> > On Sun, Aug 30, 2020, 13:11 Tatsuo Ishii <ishii at sraoss.co.jp>
>> wrote:
>> >>>>> >
>> >>>>> >> 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
>> >>>>> >> >> >>> >>
>> >>>>> >> >> >>>
>> >>>>> >> >> >>
>> >>>>> >> >>
>> >>>>> >>
>> >>>>>
>> >>> _______________________________________________
>> >>> pgpool-general mailing list
>> >>> pgpool-general at pgpool.net
>> >>> http://www.pgpool.net/mailman/listinfo/pgpool-general
>> > _______________________________________________
>> > pgpool-general mailing list
>> > pgpool-general at pgpool.net
>> > http://www.pgpool.net/mailman/listinfo/pgpool-general
>>
More information about the pgpool-general
mailing list