From: Tom Lane <tgl@sss.pgh.pa.us>
To: Michael Paquier <michael@paquier.xyz>
Cc: pgsql-hackers@lists.postgresql.org
Subject: Re: Gripes about walsender command processing
Date: Tue, 15 Sep 2020 14:48:55 -0400
Message-ID: <1347966.1600195735@sss.pgh.pa.us> (raw)
In-Reply-To: <20200915050655.GN2183@paquier.xyz>
References: <880181.1600026471@sss.pgh.pa.us>
<20200914080454.GE2183@paquier.xyz>
<1122166.1600102299@sss.pgh.pa.us>
<20200915032215.GM2183@paquier.xyz>
<1236185.1600140884@sss.pgh.pa.us>
<20200915050655.GN2183@paquier.xyz>
Michael Paquier <michael@paquier.xyz> writes:
> On Mon, Sep 14, 2020 at 11:34:44PM -0400, Tom Lane wrote:
>> (I don't quite follow your comment about repslot drop, btw.)
> There is already a command tag equivalent to DROP_REPLICATION_SLOT:
> $ git grep REPLICATION -- */cmdtaglist.h
> src/include/tcop/cmdtaglist.h:PG_CMDTAG(CMDTAG_DROP_REPLICATION_SLOT,
> "DROP REPLICATION SLOT", false, false, false)
[ blink ... ] So why is it that DropReplicationSlot does
SetQueryCompletion(&qc, CMDTAG_DROP_REPLICATION_SLOT, 0);
EndCommand(&qc, DestRemote, false);
when the caller will immediately after that do
SetQueryCompletion(&qc, CMDTAG_SELECT, 0);
EndCommand(&qc, DestRemote, true);
StartLogicalReplication has a similar weirdness.
The more I look at this code, the more broken it seems.
Anyway, independently of whether walsender should be sending multiple
command-complete messages, I don't think I really approve of including
replication commands in the CommandTag enum. It still seems like a
type pun. However, it looks like we'd have to duplicate
SetQueryCompletion/EndCommand if we don't want to do that, so maybe
I'd better just hold my nose and do it that way.
regards, tom lane
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To: pgsql-hackers@postgresql.org
Cc: tgl@sss.pgh.pa.us, michael@paquier.xyz, pgsql-hackers@lists.postgresql.org
Subject: Re: Gripes about walsender command processing
In-Reply-To: <1347966.1600195735@sss.pgh.pa.us>
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