Re: Allow "snapshot too old" error, to prevent bloat - Mailing list pgsql-hackers

From Andrew Dunstan
Subject Re: Allow "snapshot too old" error, to prevent bloat
Date
Msg-id 54EA75D0.9090402@dunslane.net
Whole thread Raw
In response to Re: Allow "snapshot too old" error, to prevent bloat  (Kevin Grittner <kgrittn@ymail.com>)
List pgsql-hackers
On 02/22/2015 11:48 AM, Kevin Grittner wrote:
>
> (2) Use a course enough granularity on time and a short enough
> maximum for the GUC to just keep a circular buffer of the mappings
> in memory.  We might be able to make this dense enough that one
> minute resolution for up to 60 days could fit in 338kB.  Obviously
> that could be reduced with courser granularity or a shorter
> maximum.
>


This doesn't sound too bad to me. Presumably these would be tunable. I 
think one minute granularity would be fine for most purposes,  but I can 
imagine people who would want it finer, like 10 seconds, say.


cheers

andrew



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