Re: Streaming Replication Networking Best Practices?

On Mon, May 14, 2018 at 11:17 AM, Flavio Henrique Araque Gurgel <
fhagur(at)gmail(dot)com> wrote:

>
> If you're running 9.6, you can use replication slots to avoid to mess with
> wal_keep_segments [1]
>

I don't think replication slots would help here. As I mentioned in my
original post, I changed wal_keep_files so that the WAL files weren't
deleted too soon, but the streaming was still slow and lagged even further
behind. My understanding is replication slots just serve to keep the WAL
files in place. If I did that then they'd probably fill up the primary disk
since the DR replica would take too long to process them all.

> Be aware that not only network bandwidth and latency are responsable for
> that behaviour, wal_receiver, disk write capability on your standby can be
> bottlenecks too.
> It happens to me in local networks with 10Gbps capable hardware.
>

Worth looking into. I would have assumed that since our local replica
handles the storage I/O just fine that the replica would since they use the
same model of hardware for server and storage array. I'll make sure that my
assumptions are correct though and see if anything else is up there.

Thanks!
Don.

--
Don Seiler
www.seiler.us