Re: Helper functions for wait_for_catchup() in Cluster.pm

Hi,

On 2/13/23 11:58 AM, Alvaro Herrera wrote:
> On 2023-Jan-26, Drouvot, Bertrand wrote:
>
>> Hi,
>>
>> On 1/26/23 10:42 AM, Alvaro Herrera wrote:
>>> On 2023-Jan-26, Drouvot, Bertrand wrote:
>>>
>>>> On 1/24/23 7:27 PM, Alvaro Herrera wrote:
>>>
>>>>> 1. I don't think wait_for_write_catchup is necessary, because
>>>>> calling wait_for_catchup() and omitting the 'mode' and 'lsn' arguments
>>>>> would already do the same thing.
>>
>> Having a closer look, it does not seem to be the case. The default mode
>> in wait_for_catchup() is 'replay' and the default mode for the lsn is 'write'.
>>
>> But in wait_for_write_catchup() we are making use of 'write' for both.
>
> But that turns
> $node->wait_for_catchup('foobar', 'write')
> into
> $node->wait_for_write_catchup('foobar');
> so I don't see much value in it.

Agree.

> Also, the patch series from which this
> patch spawned in the first place doesn't wait for write AFAICS.
>

Right, it does wait for replay only.

> After adding some more POD docs for it, I pushed the one for replay.
>

Thanks!

Regards,

--
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com