Re: Core team statement on replication in PostgreSQL

"Jeff Davis" <pgsql@j-davis.com> writes:

> On Wed, 2008-06-04 at 14:17 +0300, Heikki Linnakangas wrote:
>> > Would that also cover possible differences in page size, 32bit OS vs.
>> > 64bit OS, different timestamp flavour, etc. issues ? AFAIR, all these
>> > things can have an influence on how the data is written and possibly
>> > make the WAL incompatible with other postgres instances, even if the
>> > exact same version...
>> 
>> These are already covered by the information in pg_control.
>
> Another thing that can change between systems is the collation behavior,
> which can corrupt indexes (and other bad things).

Well, yes and no. It's entirely possible, for example, for a minor release of
an OS to tweak the collation rules for a collation without changing the name.
For the sake of argument they might just be fixing a bug in the collation
rules. From the point of view of the OS that's a minor bug fix that they might
not foresee causing data corruption problems.

Pegging pg_control to a particular release of the OS would be pretty terrible
though. I don't really see an out for this. But it's another roadblock to
consider akin to "not-really-immutable index expressions" for any proposal
which depends on re-finding index pointers :(

--  Gregory Stark EnterpriseDB          http://www.enterprisedb.com Ask me about EnterpriseDB's Slony Replication
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