Re: max_wal_size

Hello,

On 02.06.2020 22:35, Bruce Momjian wrote:
> On Thu, May 28, 2020 at 12:21:14PM +0300, p.luzanov@postgrespro.ru wrote:
>> WAL |-----------|-----+-----|-----+-----|-----+----->
>>
>>                     a           b           c
>> CP              +-----+     +-----+     +-----+
>>                  b     e     b     e     b     e
>>
>> Checkpointer process for point A starts at a(b) and ends at a(e).
>> At the end of the work, CP makes a WAL record(plus symbol on WAL line).
>>
>> Back to the max_wal_size description:
>> "Maximum size to let the WAL grow to between automatic WAL checkpoints."
>>
>> As I understand now, this is true when we talk about the checkpoint as a
>> process.
>> "Maximum size to let the WAL grow to between a(b) and b(e), between b(b) and c
>> (e), etc".
> What if we say:
>
>     "Maximum size to let the WAL grow during automatic WAL checkpoints."
>
> That highlights the "process" part.
>
Really, "during" is associated with the process, while "between" with 
points.

If there is no objection, simpe patch attached.

-----
Pavel Luzanov
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company