Re: Remove non-fast promotion Re: Should we remove a fallback promotion? take 2

Fujii Masao <masao.fujii@oss.nttdata.com>

From: Fujii Masao <masao.fujii@oss.nttdata.com>
To: Michael Paquier <michael@paquier.xyz>
Cc: Andres Freund <andres@anarazel.de>, Alvaro Herrera <alvherre@2ndquadrant.com>, Robert Haas <robertmhaas@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2020-04-21T06:29:54Z
Lists: pgsql-hackers

On 2020/04/21 14:54, Michael Paquier wrote:
> On Tue, Apr 21, 2020 at 02:27:20PM +0900, Fujii Masao wrote:
>> On 2020/04/21 10:59, Michael Paquier wrote:
>>> With your patch, this code
>>> now means that in order to finish recovery you need to send SIGUSR2 to
>>> the startup process *and* to create the promote signal file.
>>
>> Yes, but isn't this the same as the way to trigger fast promotion in HEAD?
> 
> Yep, but my point is that some users who have been relying only on
> SIGUSR2 sent to the startup process for a promotion may be surprised
> to see that doing the same operation does not trigger a promotion
> anymore.

Yeah, but that's not documented. So I don't think that we need to keep
the backward-compatibility for that.

Also in that case, non-fast promotion is triggered. Since my patch
tries to remove non-fast promotion, it's intentional to prevent them
from doing that. But you think that we should not drop that because
there are still some users for that?

Regards,

-- 
Fujii Masao
Advanced Computing Technology Center
Research and Development Headquarters
NTT DATA CORPORATION



Commits

  1. Remove non-fast promotion.