Hi,
On 2014-04-16 18:51:41 +0200, Magnus Hagander wrote:
> I'm thinking it could be interesting to know how many times (or in some
> other useful unit than "times" - how often) a specific replication slot has
> "blocked" xlog rotation. Since this AFAIK only happens during checkpoints,
> it seems it should be "reasonably cheap" to track? It would serve as an
> indicator of which slave(s) are having enough trouble keeping up to
> potentially cause issues.
The xlog removal code just check the "global minimum" required LSN - it
doesn't check the individual slots. So you'd need to add a bit more code
to that location. But it'd be easy.
But I think I'd just monitor/graph the byte difference for all slots
using pg_replication_slots...
Greetings,
Andres Freund
-- Andres Freund http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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