Re: pg_control is missing a field for LOBLKSIZE

On Tue, Jun 17, 2014 at 8:46 PM, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
> On Tue, Jun 17, 2014 at 07:12:16PM -0400, Tom Lane wrote:
>> Bruce Momjian <bruce(at)momjian(dot)us> writes:
>> > On Tue, Jun 17, 2014 at 03:55:02PM -0400, Alvaro Herrera wrote:
>> >> Can't you compare it to the historic default value? I mean, add an
>> >> assumption that people thus far has never tweaked it.
>>
>> > Well, if they did tweak it, then they would be unable to use pg_upgrade
>> > because it would complain about a mismatch if they actually matched the
>> > old and new servers.
>>
>> What about comparing to the symbolic value LOBLKSIZE? This would make
>> pg_upgrade assume that the old installation had been tweaked the same
>> as in its own build. This ends up being the same as what you said,
>> ie, effectively no comparison ... but it might be less complicated to
>> code/understand.
>
> OK, assume the compiled-in default is the value for an old cluster that
> has no value --- yeah, I could do that.

I'm not really sure why this is better than Bruce's original proposal, though.

--
Robert Haas
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