Re: max_wal_size

On Thu, May 28, 2020 at 12:21:14PM +0300, p(dot)luzanov(at)postgrespro(dot)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.

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Bruce Momjian <bruce(at)momjian(dot)us> https://momjian.us
EnterpriseDB https://enterprisedb.com

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