Re: Wrong defeinition of pq_putmessage_noblock since 9.5 - Mailing list pgsql-hackers

From Kyotaro HORIGUCHI
Subject Re: Wrong defeinition of pq_putmessage_noblock since 9.5
Date
Msg-id 20160729.145512.44798004.horiguchi.kyotaro@lab.ntt.co.jp
Whole thread Raw
In response to Re: Wrong defeinition of pq_putmessage_noblock since 9.5  (Michael Paquier <michael.paquier@gmail.com>)
Responses Re: Wrong defeinition of pq_putmessage_noblock since 9.5
List pgsql-hackers
At Fri, 29 Jul 2016 12:47:53 +0900, Michael Paquier <michael.paquier@gmail.com> wrote in
<CAB7nPqSSNTroRi=zGMDxYa7PzX_VSck6hbHY6eTnBBsfYaah6A@mail.gmail.com>
> On Fri, Jul 29, 2016 at 12:18 PM, Kyotaro HORIGUCHI
> <horiguchi.kyotaro@lab.ntt.co.jp> wrote:
> > At Thu, 28 Jul 2016 10:46:00 -0400, Tom Lane <tgl@sss.pgh.pa.us> wrote in <4313.1469717160@sss.pgh.pa.us>
> >> Fujii Masao <masao.fujii@gmail.com> writes:
> >> > 3. Several source comments in pqcomm.c have not been updated.
> >> >     Some comments still use the old function name like pq_putmessage().
> >>
> >> > Attached patch fixes the above issues.
> >>
> >> I dunno, this seems like it's doubling down on some extremely poor
> >> decisions.  Why is it that you now have to flip a coin to guess whether
> >> the prefix is pq_ or socket_ for functions in this module?  I would
> >> rather see that renaming reverted.
> 
> Yes, I agree with that. I cannot understand the intention behind
> 2bd9e41 to rename those routines as they are now, so getting them back
> with pg_ as prefix looks like a good idea to me.

The many of the socket_* functions are required to be replaced
with mq_* functions for backgroud workers. So reverting the names
of socket_* functions should be accompanied by the need to, for
example, changing their callers to use them explicitly via
PqCommMethods, not hiding with macros, or renaming current pq_*
macros to, say, pqi_. (it stands for PQ-Indirect as a tentative)
I'm not confident on the new prefix since I'm not sure that what
the 'pq' stands for. (Postgres Query?)

Attached patch is a rush work to revert the names of socket_
functions and replace the prefix of the macros with "pqi". pq_
names no longer points to mq_ functions. Is this roughly on the
right way? Even though the prefix is not appropriate.

> > The set of functions in PQcommMethods doesn't seem clean. They
> > are chosen arbitrarily just so that other pq_* functions used in
> > parallel workers will work as expected. I suppose that it needs
> > some refactoring.
> 
> Any work in this area is likely 10.0 material at this point.
> 
> > By the way, pq_start/endcopyout() are used only in FE protocols
> > below 3.0, which had already bacome obsolete as of PG7.4. While
> > the next dev cycle is for PG10, if there is no particular reason
> > to support such ancient protocols, removing them would make things
> > easier and cleaner.
> 
> Remove support for protocol 2 has been in the air for some time, but
> that's a separate discussion. If you want to discuss this issue
> particularly, raising a new thread would be a good idea.

Thanks. I saw in somewhere that the protocol 2 no longer
works. I'll raise a new thread later.

regards,

-- 
Kyotaro Horiguchi
NTT Open Source Software Center

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