On Wed, Apr 10, 2013 at 11:56 PM, Tom Lane wrote:
> Gurjeet Singh writes:
> > So, again, it is not guaranteed that all the scans on a relation will
> > synchronize with each other. Hence my proposal to include the term
> > 'probability' in the definition.
>
> Yeah, it's definitely not "guarantee
Gurjeet Singh writes:
> On Wed, Apr 10, 2013 at 11:10 PM, Tom Lane wrote:
>> The point you're missing is that the synchronization is self-enforcing:
> Let's consider a pathological case where a scan is performed by a user
> controlled cursor, whose scan speed depends on how fast the user presses
On Wed, Apr 10, 2013 at 11:10 PM, Tom Lane wrote:
> Gurjeet Singh writes:
> > If I'm reading the code right [1], this GUC does not actually
> *synchronize*
> > the scans, but instead just makes sure that a new scan starts from a
> block
> > that was reported by some other backend performing a sc
Gurjeet Singh writes:
> If I'm reading the code right [1], this GUC does not actually *synchronize*
> the scans, but instead just makes sure that a new scan starts from a block
> that was reported by some other backend performing a scan on the same
> relation.
Well, that's the only *direct* effec
