Re: [HACKERS] Logical Replication WIP

On 1/15/17 1:48 PM, Petr Jelinek wrote:
> It's meant to decouple the synchronous commit setting for logical
> replication workers from the one set for normal clients. Now that we
> have owners for subscription and subscription runs as that owner, maybe
> we could do that via ALTER USER.

I was thinking about that as well.

> However I think the apply should by
> default run with sync commit turned off as the performance benefits are
> important there given that there is one worker that has to replicate in
> serialized manner and the success of replication is not confirmed by
> responding to COMMIT but by reporting LSNs of various replication stages.

Hmm, I don't think we should ship with an "unsafe" default.  Do we have
any measurements of the performance impact?

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
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