[pgpool-hackers: 2829] Re: Proposal: Add last state change timestamp to "show pool_nodes"

Muhammad Usama m.usama at gmail.com
Tue Jun 12 18:19:43 JST 2018


Hi Ishii-San,

On Tue, Jun 12, 2018 at 5:47 AM Tatsuo Ishii <ishii at sraoss.co.jp> wrote:

> Hi Usama,
>
> > Hi Ishii-San
> >
> > Thanks for the patch and I totally second the Peng's comment that it is a
> > very useful feature
> > to have and will have many practical use cases.
> > I have couple of small comments on the attached patch
> > One is I think it would be good idea to also include this last status
> > changed column in pcp_node_info's output.
>
> If we do that we need to maintain pgpool_adm as well. Pgpool_adm is
> already far behind from current pcp_node_info implementation since
> pgpool_adm lacks "backend role" column.
>
>
Yes that is one issue, and I believe we need to plan out something for
Pgpool-adm
enhancement to bring it upto Pgpool core version.
I am just thinking Is it possible if  we add the last_status_change column
in pcp_node_info
but Pgpool_adm keep ignoring it until it is updated



> > and secondly what do you think about renaming the "status_changed" column
> > name to "last status change"  in
> > show pool_nodes output?
>
> Maybe but "last status change" is not appropreate column name. It
> should be "last_status_change" or something like that.
>

Sorry for the type. I actually meant "last_status_change" :-)

Thanks
Best regards
Muhammad Usama

>
> > Thanks
> > Best Regards
> > Muhammad Usama
> >
> >
> > On Mon, Jun 11, 2018 at 7:14 PM Tatsuo Ishii <ishii at sraoss.co.jp> wrote:
> >
> >> > Hi Ishii-san,
> >> >
> >> > I think this will be useful to show the last state change timestamp.
> >>
> >
> > Totally agree. This will be a very useful feature to have.
> >
> >>
> >> Thanks. Attached is a patch to implement this. Still documentations
> >> need to be updated.
> >>
> >> > When pgpool-II starts, the timestamp is set to time the startup
> >> > time. After that whenever the status is changed, time timestamp is
> >> > recorded and shown.
> >>
> >> Here "status" means not only "up" and "down" etc. but primary node
> >> changes. For example suppose there are two nodes 0 (primary) and 1
> >> (standby). If node 0 goes down and node 1 is promoted to primary, the
> >> time stamp of node 1 is updated. Though the up/down status of node 1
> >> is not changed (up->up), it becomes primary from standby.
> >>
> >> Here is an example output of "show pool_nodes".
> >>
> >> test=# show pool_nodes;
> >> -[ RECORD 1 ]-----+--------------------
> >> node_id           | 0
> >> hostname          | /tmp
> >> port              | 11002
> >> status            | up
> >> lb_weight         | 0.500000
> >> role              | standby
> >> select_cnt        | 0
> >> load_balance_node | true
> >> replication_delay | 0
> >> status_changed    | 2018-06-11 23:11:45
> >> -[ RECORD 2 ]-----+--------------------
> >> node_id           | 1
> >> hostname          | /tmp
> >> port              | 11003
> >> status            | up
> >> lb_weight         | 0.500000
> >> role              | primary
> >> select_cnt        | 0
> >> load_balance_node | false
> >> replication_delay | 0
> >> status_changed    | 2018-06-11 23:11:45
> >>
> >> Best regards,
> >> --
> >> Tatsuo Ishii
> >> SRA OSS, Inc. Japan
> >> English: http://www.sraoss.co.jp/index_en.php
> >> Japanese:http://www.sraoss.co.jp
> >> _______________________________________________
> >> pgpool-hackers mailing list
> >> pgpool-hackers at pgpool.net
> >> http://www.pgpool.net/mailman/listinfo/pgpool-hackers
> >>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.sraoss.jp/pipermail/pgpool-hackers/attachments/20180612/fe60e8aa/attachment.html>


More information about the pgpool-hackers mailing list