Subject: Re: The description for pg_replication_slots.restart_lsn
From: Fujii Masao <masao.fujii@oss.nttdata.com>
To: pgsql-docs@lists.postgresql.org
References: <6497f1e9-3148-c5da-7e49-b2fddad9a42f@oss.nttdata.com>
Message-ID: <d6517043-606c-a953-bc66-bca101c5a604@oss.nttdata.com>
Date: Thu, 25 Jun 2020 09:42:47 +0900
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On 2020/06/17 23:47, Fujii Masao wrote:
> Hi,
> 
> The document explains that restart_lsn column in pg_replication_slots view is:
> 
>      The address (LSN) of oldest WAL which still might be required by
>      the consumer of this slot and thus won't be automatically removed
>      during checkpoints.
> 
> But the latter part is not true in v13 thanks to max_slot_wal_keep_size.
> I think that we need to update it as follows. Thought?
> 
>      The address (LSN) of oldest WAL which still might be required by
>      the consumer of this slot and thus won't be automatically removed
>      during checkpoints unless this LSN gets behind more than
>      max_slot_wal_keep_size from the current LSN.
> 
> Patch attached.

Barring any objection, I will commit this patch.

Regards,


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