Re: Allow "snapshot too old" error, to prevent bloat

On 2015-02-16 16:35:46 -0500, Bruce Momjian wrote:
> It seems we already have a mechanism in place that allows tuning of
> query cancel on standbys vs. preventing standby queries from seeing old
> data, specifically
> max_standby_streaming_delay/max_standby_archive_delay.  We obsessed
> about how users were going to react to these odd variables, but there
> has been little negative feedback.

FWIW, I think that's a somewhat skewed perception. I think it was right to
introduce those, because we didn't really have any alternatives.

But max_standby_streaming_delay, max_standby_archive_delay and
hot_standby_feedback are among the most frequent triggers for questions
and complaints that I/we see.

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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