Re: Proposed patch: Smooth replication during VACUUM FULL

On Mon, May 2, 2011 at 3:37 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Simon Riggs <simon(at)2ndQuadrant(dot)com> writes:
>> I can't see the objection to replacing something inadvertently removed
>> in 9.0, especially since it is a 1 line patch and is accompanied by
>> copious technical evidence.
>
> I am not sure which part of "this isn't a substitute for what happened
> before 9.0" you fail to understand.
>
> As for "copious technical evidence", I saw no evidence provided
> whatsoever that this patch really did anything much to fix the
> reported problem.

Just so we're looking at the same data, graph attached.

> Yeah, it would help during the initial scan
> of the old rel, but not during the sort or reindex steps.

As Greg points out, the sort is not really of concern (for now).

> (And as for the thoroughness of the technical analysis, the patch
> doesn't even catch the second CHECK_FOR_INTERRUPTS in copy_heap_data;
> which would at least provide some relief for the sort part of the
> problem, though only in the last pass of sorting.)

I'm sure Gabriele can add those things as well - that also looks like
another 1 line change.

I'm just observing that the patch as-is appears effective and I feel
it is important.

--
 Simon Riggs                   http://www.2ndQuadrant.com/
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