On Sat, Feb 13, 2016 at 2:39 PM, Andres Freund <andres@anarazel.de> wrote:
On 2016-02-13 22:37:33 +0900, Michael Paquier wrote: > On Sat, Feb 13, 2016 at 10:15 PM, Magnus Hagander wrote: > > So, I suggest the following changes to the defaults: > > wal_level=hot_standby > > max_wal_senders=10 > > max_replication_slots=10
+1. I'm inclined to set slots a bit higher than senders. They're pretty cheap...
So something like 10/20?
I think this is way past due. > 10 seems a bit high. I would think that max_wal_senders and > max_replication_slots set at 3 are sufficient enough, giving enough > room for simple deployments willing to use replication.
But they're relatively cheap to enable, so why set them low?
That's my reasoning as well. I think you will be hard pressed to even measure the overhead between 3 and 10. The big difference will be in leaving 0 and in particular setting wal_level.