Re: [9.4] Make full_page_writes only settable on server start?

On 2013-09-04 07:57:15 -0700, Jeff Davis wrote:
> XLogSaveBufferForHint() calls XLogCheckBuffer() but doesn't also look at
> the full page writes setting (like in XLogInsert()). That means, if
> checksums are enabled and full_page_writes is off, we'll still write
> some full page images for checksums. I'd like to remedy that.

I don't think that's really as easy as it sounds without removing the
ability to do base backups with full_page_writes = off. The interlocking
that would require makes things complex...
Personally I'd rather forbid enabling checkpoints in the combination
with full_page_writes = off. That doesn't seem like a good idea to me
and I am far from convinced it's actually going to work in all corner cases.

Greetings,

Andres Freund

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