Re: Support for N synchronous standby servers - take 2

Michael Paquier wrote:
> On Fri, Jan 8, 2016 at 1:53 PM, Kyotaro HORIGUCHI
> <horiguchi(dot)kyotaro(at)lab(dot)ntt(dot)co(dot)jp> wrote:
> > Hello,
> >
> > At Mon, 4 Jan 2016 15:29:34 +0900, Michael Paquier <michael(dot)paquier(at)gmail(dot)com> wrote in <CAB7nPqTp5RoHxcp8YxejGMjRjjtLaXCa8=-BEr7ZnBNbPzPdWA(at)mail(dot)gmail(dot)com>
> >>
> >> Something that I find rather scary with this patch: could it be
> >> possible to get actual regression tests now that there is more
> >> machinery with PostgresNode.pm? As syncrep code paths get more and
> >> more complex, so are debugging and maintenance.
> >
> > The test on the whole replication system will very likely to be
> > too complex and hard to stabilize, and would be
> > disproportionately large to other tests.
>
> I don't buy that much. Mind you, there is in this commit fest a patch
> introducing a basic regression test suite for recovery using the new
> infrastructure that has been committed last month. You may want to
> look at it.

Kyotaro, please have a look at this patch:
https://commitfest.postgresql.org/8/438/
which is the recovery test framework Michael is talking about. Is it
possible to use that framework to write tests for this feature? If so,
then my preferred course of action would be to commit that patch and
then introduce in this patch some additional tests for the N-sync-standby
feature. Can you please have a look at the test framework patch and
provide your feedback on how usable it is for this?

Thanks,

--
Álvaro Herrera http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services