[pgpool-general: 3315] Re: Weight

[Tatsuo Ishii]

Yes. If "standby" is specified by the parameter, pgpool-II will choose
one of standby nodes taking consideration of "weight" paramter.

Best regards,
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese:http://www.sraoss.co.jp

> Oh!
> 
> Could this new setting be used to achieve my previous example?
> 
> So have read weights for all, and use this?
> 
> Cheers,
> 
> 
> James Sewell,
> PostgreSQL Team Lead / Solutions Architect
> ______________________________________
> 
> 
>  Level 2, 50 Queen St, Melbourne VIC 3000
> 
> *P *(+61) 3 8370 8000  *W* www.lisasoft.com  *F *(+61) 3 8370 8099
> 
> 
> On Tue, Nov 25, 2014 at 11:57 AM, Tatsuo Ishii <ishii at postgresql.org> wrote:
> 
>> BTW from pgpool-II 3.4.0, you could achieve this by using new parameter.
>>
>> database_redirect_preference_list = '.*:standby'
>>
>> This will redirect all read only SELECTs to the standby (or one of
>> standbys if you have multiple of them) regardless of the physical node
>> id of primary.
>>
>> Best regards,
>> --
>> Tatsuo Ishii
>> SRA OSS, Inc. Japan
>> English: http://www.sraoss.co.jp/index_en.php
>> Japanese:http://www.sraoss.co.jp
>>
>> > Well I think the real problem here is, the configuration of weight is
>> > bound to physical node. Ideally the weight should be bound to the
>> > "logical" or "role" of the node: primary (master) or standbye (slave).
>> > This way, you don't need to change the weight parameter after role of
>> > the nodes are swapped. What do you think?
>> >
>> > Best regards,
>> > --
>> > Tatsuo Ishii
>> > SRA OSS, Inc. Japan
>> > English: http://www.sraoss.co.jp/index_en.php
>> > Japanese:http://www.sraoss.co.jp
>> >
>> >> Hello,
>> >>
>> >> This method works well, but doesn't really play nicely with our use of
>> >> Puppet (which manages the config files).
>> >>
>> >> Would anyone support looking into a pcp command to change this? I may
>> have
>> >> some time early in the new year to have a go at an implementation.
>> >>
>> >> I was thinking a very simple:
>> >>
>> >> pcp_node_weight timeout hostname port# username password nodeID
>> newweight
>> >>
>> >> Maybe there is a reason this won't work / isn't a good idea though?
>> >>
>> >> Cheers,
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >> James Sewell,
>> >> PostgreSQL Team Lead / Solutions Architect
>> >> ______________________________________
>> >>
>> >>
>> >>  Level 2, 50 Queen St, Melbourne VIC 3000
>> >>
>> >> *P *(+61) 3 8370 8000  *W* www.lisasoft.com  *F *(+61) 3 8370 8099
>> >>
>> >>
>> >> On Tue, Jul 15, 2014 at 5:38 PM, Tatsuo Ishii <ishii at postgresql.org>
>> wrote:
>> >>
>> >>> > Hey All,
>> >>> >
>> >>> > I have two nodes setup like so:
>> >>> >
>> >>> >    - Node 1: Master, weight 0
>> >>> >    - Node 2: Slave, weight 1
>> >>> >
>> >>> > This allows me to send all writes to the master and all reads to the
>> >>> slave.
>> >>> >
>> >>> > At some stage I promote the slave to be the new master (pcp_promote
>> with
>> >>> > DISALLOW_TO_FAILOVER), then at some stage later re-provision the
>> master
>> >>> as
>> >>> > a new slave and re-connect it (pcp_enable)
>> >>> >
>> >>> > I now have the following setup:
>> >>> >
>> >>> >    - Node 1: Slave, weight 0
>> >>> >    - Node 2: Master, weight 1
>> >>> >
>> >>> > This means that all write and read queries are serviced by the new
>> >>> master,
>> >>> > and none by the new slave.
>> >>> >
>> >>> > Is there a way around this? If there isn't currently could a pcp
>> command
>> >>> be
>> >>> > implemented which would allow me to manage my own weights?
>> >>>
>> >>> You could change weight parameters in pgpool.conf then reload it.
>> >>>
>> >>> Best regards,
>> >>> --
>> >>> Tatsuo Ishii
>> >>> SRA OSS, Inc. Japan
>> >>> English: http://www.sraoss.co.jp/index_en.php
>> >>> Japanese:http://www.sraoss.co.jp
>> >>>
>> >>> > Cheers,
>> >>> >
>> >>> >
>> >>> >
>> >>> > James Sewell,
>> >>> > PostgreSQL Team Lead / Solutions Architect
>> >>> > ______________________________________
>> >>> >
>> >>> >
>> >>> >  Level 2, 50 Queen St, Melbourne VIC 3000
>> >>> >
>> >>> > *P *(+61) 3 8370 8000  *W* www.lisasoft.com  *F *(+61) 3 8370 8099
>> >>> >
>> >>> > --
>> >>> >
>> >>> >
>> >>> > ------------------------------
>> >>> > The contents of this email are confidential and may be subject to
>> legal
>> >>> or
>> >>> > professional privilege and copyright. No representation is made that
>> this
>> >>> > email is free of viruses or other defects. If you have received this
>> >>> > communication in error, you may not copy or distribute any part of
>> it or
>> >>> > otherwise disclose its contents to anyone. Please advise the sender
>> of
>> >>> your
>> >>> > incorrect receipt of this correspondence.
>> >>>
>> >>
>> >> --
>> >>
>> >>
>> >> ------------------------------
>> >> The contents of this email are confidential and may be subject to legal
>> or
>> >> professional privilege and copyright. No representation is made that
>> this
>> >> email is free of viruses or other defects. If you have received this
>> >> communication in error, you may not copy or distribute any part of it or
>> >> otherwise disclose its contents to anyone. Please advise the sender of
>> your
>> >> incorrect receipt of this correspondence.
>> > _______________________________________________
>> > pgpool-general mailing list
>> > pgpool-general at pgpool.net
>> > http://www.pgpool.net/mailman/listinfo/pgpool-general
>>
> 
> -- 
> 
> 
> ------------------------------
> The contents of this email are confidential and may be subject to legal or 
> professional privilege and copyright. No representation is made that this 
> email is free of viruses or other defects. If you have received this 
> communication in error, you may not copy or distribute any part of it or 
> otherwise disclose its contents to anyone. Please advise the sender of your 
> incorrect receipt of this correspondence.