Hi,
On 2016-10-09 21:51:07 -0700, Josh Berkus wrote:
> Given that hot_standby_feedback is pretty bulletproof now, and a lot of
> the work in reducing replay conflicts, I think the utility of
> vacuum_defer_cleanup_age is at an end. I really meant so submit a patch
> to remove it to 9.6, but it got away from me.
HS feedback doesn't e.g. work well with delayed and/or archived replay,
whereas defer_cleanup does.
On the other hand, removing it would make some of the reasoning around
GetOldestXmin() a bit easier.
Andres