Re: Stopping logical replication protocol

On 25 August 2016 at 09:22, Craig Ringer <craig(at)2ndquadrant(dot)com> wrote:
> On 25 August 2016 at 03:26, Vladimir Gordiychuk <folyga(at)gmail(dot)com> wrote:
>> Hi. It has already passed a few months but patch still have required review
>> state. Can I help to speed up the review, or should i wait commitfest?
>> I plane complete changes in pgjdbc drive inside PR
>> https://github.com/pgjdbc/pgjdbc/pull/550 but PR blocked current problem
>> with not available stop logical replication.
>
> The latest patch is the updated one I posted, which was the part of
> yours that allowed return to command mode when logical decoding is
> idle.
>
> If you want to submit an updated version of the second patch, with the
> callback to allow logical decoding cancellation during
> ReorderBufferCommit, that'd be handy, but I don't think it's as
> important as the first one.
>
> As far as I'm concerned the first patch is ready. Please take a look
> and verify that you're happy with my updates and test the updated
> patch. I'll mark it ready to go if you are. It's linked to at
> https://commitfest.postgresql.org/10/621/ .

By the way, I now think that the second part of your patch, to allow
interruption during ReorderBufferCommit processing, is also very
desirable.

Not just for that feature, but because we should be processing client
messages during long ReorderBufferCommit executions so that we can
respond to feedback from the client. Right now, long running
ReorderBufferCommit runs can trigger walsender_timeout because there's
no feedback processed.

Alternately, ReorderBufferCommit() could call back into the walsender
with a progress update, without requiring the client to send feedback.
It knows the client is making progress because it's consuming data on
the socket. But I'd rather have client feedback processed, since it
could be useful later for client=->server messages to output plugin
callbacks too.

--
Craig Ringer http://www.2ndQuadrant.com/
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