Re: [bug fix] Cascading standby cannot catch up and get stuck emitting the same message repeatedly

Tsunakawa, Takayuki <tsunakawa.takay@jp.fujitsu.com>

From: "Tsunakawa, Takayuki" <tsunakawa.takay@jp.fujitsu.com>
To: 'Robert Haas' <robertmhaas@gmail.com>
Cc: "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2016-11-15T03:25:22Z
Lists: pgsql-hackers

Attachments

From: pgsql-hackers-owner@postgresql.org
> [mailto:pgsql-hackers-owner@postgresql.org] On Behalf Of Robert Haas
> Let me try to be more clear.  I will not commit this patch if it is not
> properly commented.  I doubt that anyone else will, either.
> 
> The fact that those code changes already exist in 9.4+ is not a reason to
> back-port them to earlier releases without a proper explanation of why we
> are doing it.  Very possibly, we should also improve the comments in newer
> branches so that future authors don't reintroduce whatever bugs were fixed
> by these changes.  But whether we do that or not, I am not going to commit
> uncommented patches to complex code in order to fix obscure bugs in
> 3+-year-old branches.  I think that is a non-starter.
> 

OK, although I'm not perfectly sure what to add as a comment, I added an example scenario as a comment because I thought a concrete situation helps to understand the existing two paragraphs.  Is this good?

Regards
Takayuki Tsunakawa

Commits

  1. Fix bug in verifying TLI (timeline ID) in WAL page header during recovery..

  2. Split out XLog reading as an independent facility