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Date: Wed, 24 Apr 2024 10:57:21 +0200
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Subject: Re: wal_init_zero / wal_recycle
To: Nicolas Seinlet <nicolas@seinlet.eu>,
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From: Peter Eisentraut <peter@eisentraut.org>
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On 24.04.24 10:08, Nicolas Seinlet wrote:
> while searching the doc to solve an issue, I found the interdependency 
> between those 2 parameters was not obvious.
> 
> Here:
> https://www.postgresql.org/docs/14/runtime-config-wal.html#GUC-WAL-INIT-ZERO <https://www.postgresql.org/docs/14/runtime-config-wal.html#GUC-WAL-INIT-ZERO>
> 
> the wal_init_zero set to ON cause new WAL files to be filled with zeroes.
> 
> It was not crystal clear to me that when wal_recycle is also ON , the 
> recycled files are not filled with zeroes, because they are not 
> considered as new. Could we add a sentence stating this?

It currently says:

wal_init_zero: "... causes new WAL files to be filled with zeroes ..."

wal_recycle: "... avoiding the need to create new ones ..."

I'm not sure where exactly to make that more clear.