Date: Wed, 24 Mar 2021 13:39:31 -0300
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Fujii Masao <masao.fujii@oss.nttdata.com>
Cc: zoulx1982@163.com, pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #16931: source code problem about commit_ts
Message-ID: <20210324163931.GA24841@alvherre.pgsql>
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On 2021-Mar-24, Fujii Masao wrote:

> On 2021/03/24 18:05, Alvaro Herrera wrote:
> > Yeah, it seems like a bug.  With your patch, the write_xlog=true path
> > becomes unused, and thus the whole COMMIT_TS_SETTS record, so we could
> > remove those things in branch master.  The timestamp is acquired from
> > the COMMIT record.
> 
> I agree to remove COMMIT_TS_SETTS record from the master branch
> if there are no users or extensions of it. Patch attached.

Looks good in a quick skim.  Let's get this pushed quickly; if anything
exists out there that is calling that code, it'd be good to know sooner
rather than later.  However, my feeling is that no such caller exists,
because they would have told us about this problem already.

Are you bumping WAL page magic?  It'd be logical to do so, but on the
other hand if no code exists that is capable of emitting that record,
then it'd be pointless.

> Anyway, at first, what about applying the bugfix patch I posted upthread
> to all supported branches?

Yeah, let's do that.


-- 
Álvaro Herrera                            39°49'30"S 73°17'W
"XML!" Exclaimed C++.  "What are you doing here? You're not a programming
language."
"Tell that to the people who use me," said XML.
https://burningbird.net/the-parable-of-the-languages/