Re: libpq changes for synchronous replication

On Mon, Nov 15, 2010 at 7:26 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
>> On Mon, Sep 20, 2010 at 12:17 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>>> Personally I think this demonstrates that piggybacking replication
>>> data transfer on the COPY protocol was a bad design to start with.
>>> It's probably time to split them apart.
>
>> This appears to be the only obvious unresolved issue regarding this patch:
>
>> https://commitfest.postgresql.org/action/patch_view?id=412
>
>> I don't have a strong personal position on whether or not we should do
>> this, but it strikes me that Tom hasn't given much justification for
>> why he thinks we should do this, what benefit we'd get from it, or
>> what the design should look like.  So I guess the question is whether
>> Tom - or anyone - would like to make a case for a more serious
>> protocol overhaul, or whether we should just go with the approach
>> proposed here.
>
> I was objecting to v1 of the patch.  v2 seems somewhat cleaner --- it at
> least avoids changing the behavior of libpq for normal COPY operation.
> I'm still a bit concerned by the prospect of having to shove further
> warts into the COPY data path in future, but maybe its premature to
> complain about that when it hasn't happened yet.

It's not an unreasonable complaint, but I don't have a very clear idea
what to do about it.

> Just in a quick scan, I don't have any objection to v2 except that the
> protocol documentation is lacking.

OK, I'll mark it Waiting on Author pending that issue.

--
Robert Haas
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