Re: Enable WAL archiving even in standby

On 13 August 2014 11:42, Fujii Masao <masao.fujii@gmail.com> wrote:

> I'd propose the attached WIP patch which allows us to enable WAL archiving
> even in standby. The patch adds "always" as the valid value of archive_mode.
> If it's set to "always", the archiver is started when the server is in standby
> mode and all the WAL files that walreceiver wrote to the disk are archived by
> using archive_command. Then, even after the server is promoted to master,
> the archiver keeps archiving WAL files. The patch doesn't change the meanings
> of the setting values "on" and "off" of archive_mode.

Seems OK idea.

Perhaps better to have a new parameter called  archive_role = Origin | Replica | Always should be used so we match
up with how triggers/rules work.
rather than abuse archive_mode

We can pass a attribute called %m (mode?) which tells the
archive_command whether we are Master or Standby when called

Remember to bump the number of background procs by 1 since we
previously assumed archiver would never run in recovery

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