Re: Re: BUG #13685: Archiving while idle every archive_timeout with wal_level hot_standby

On Fri, Nov 6, 2015 at 2:47 AM, Michael Paquier
<michael.paquier@gmail.com> wrote:
> I have as well thought a bit about adding a space-related constraint
> on the standby snapshot generated by the bgwriter, so as to not rely
> entirely on the interval of 15s. I finished with the attached that
> uses a check based on CheckPointSegments / 8 to be sure that at least
> this number of segments has been generated since the last checkpoint
> before logging a new snapshot. I guess that's less brittle than the
> last patch. Thoughts?

I can't see why that would be a good idea.  My understanding is that
the logical decoding code needs to get those messages pretty
regularly, and I don't see why that need would be reduced on systems
where CheckPointSegments is large.

-- 
Robert Haas
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