[pgpool-general: 710] Re: SR+load balance: Cannot execute SELECT FOR UPDATE in a read-only transaction

Isengard from.isengard at googlemail.com
Fri Jul 6 21:45:20 JST 2012


Yes,
we never set the standby address in the application, so there is no
way to connect directly to standby server.
If you want more log/debug information, I can send..
The application that causes this error is http://quartz-scheduler.org/

On Thu, Jul 5, 2012 at 10:18 PM, Tatsuo Ishii <ishii at postgresql.org> wrote:
> Are you sure that the query was sent from pgpool?
> --
> Tatsuo Ishii
> SRA OSS, Inc. Japan
> English: http://www.sraoss.co.jp/index_en.php
> Japanese: http://www.sraoss.co.jp
>
>> My standby server is logging this error:
>>> Error: cannot execute SELECT FOR UPDATE in a read-only transaction
>>> SELECT * FROM QRTZ_LOCKS WHERE LOCK_NAME = $1 FOR UPDATE;
>>
>> Any idea on how/why pgpool is sending a "SELECT..FOR UPDATE" to standby?
>>
>> It seems the query is not inside a function, at least the error
>> message does not show that.
>> It's a third-party software, so I do not have access to the source-code.
>>
>>>From pgpool-ii docs:
>>> For a query to be load balanced, all the following requirements must be met:
>>>  > it's not SELECT FOR UPDATE nor FOR SHARE
>>
>>
>> [pgpool.conf]
>> load_balance_mode = on
>> ignore_leading_white_space = on
>> white_function_list = ''
>> black_function_list = 'currval,lastval,nextval,setval'
>> master_slave_mode = on
>> master_slave_sub_mode = 'stream'
>> sr_check_period = 10
>> sr_check_user = 'pgpoolstream'
>> sr_check_password = 'xxx'
>> delay_threshold = 10000000
>> follow_master_command = ''
>>
>> # pgpool --version
>> pgpool-II version 3.1.3 (hatsuiboshi)
>> # uname -a
>> Linux 2.6.18-194.el5 #1 SMP Fri Apr 2 14:58:14
>> EDT 2010 x86_64 x86_64 x86_64 GNU/Linux
>> # cat /etc/redhat-release
>> CentOS release 5.5 (Final)
>>
>> thanks
>> _______________________________________________
>> 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