Re: Switching XLog source from archive to streaming when primary available - Mailing list pgsql-hackers

On Tue, Mar 05, 2024 at 11:38:37PM +0530, Bharath Rupireddy wrote:
> On Tue, Mar 5, 2024 at 7:34 AM Nathan Bossart <nathandbossart@gmail.com> wrote:
>> Is there any way to simplify this?  For
>> example, would it be possible to make an enum that tracks the
>> streaming_replication_retry_interval state?
> 
> I guess the way it is right now looks simple IMHO. If the suggestion
> is to have an enum like below; it looks overkill for just two states.
> 
> typedef enum
> {
>     CAN_SWITCH_SOURCE,
>     SWITCH_SOURCE
> } XLogSourceSwitchState;

I was thinking of something more like

    typedef enum
    {
        NO_FORCE_SWITCH_TO_STREAMING,        /* no switch necessary */
        FORCE_SWITCH_TO_STREAMING_PENDING,    /* exhausting pg_wal */
        FORCE_SWITCH_TO_STREAMING,            /* switch to streaming now */
    } WALSourceSwitchState;

At least, that illustrates my mental model of the process here.  IMHO
that's easier to follow than two similarly-named bool variables.

-- 
Nathan Bossart
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