Re: Re: patch: fix performance problems with repated decomprimation of varlena values in plpgsql

2011/2/8 Noah Misch <noah(at)leadboat(dot)com>:
> On Tue, Feb 08, 2011 at 10:24:03AM -0500, Robert Haas wrote:
>> Well, Pavel's subsequent reply suggested that he didn't test exactly
>> this thing, so maybe there's hope.
>
> No hope on that basis, no.
>
>> Or maybe not.  If Tom thought one branch inside exec_eval_datum() was
>> going to be too expensive, four isn't going to be better.
>
> He was commenting on a proposal equivalent to yours.  You might want to reread
> this thread in its entirety; we're coming full circle.
>
>> But I think we're out of time to work on this for this cycle.  Even if
>> my latest idea is brilliant (and it may not be), we still have to test
>> it in a variety of cases and get consensus on it, which seems like
>> more than we can manage right now.  I think it's time to mark this one
>> Returned with Feedback, or perhaps Rejected would be more accurate in
>> this instance.
>
> It's not as if this patch raised complex questions that folks need more time to
> digest.  For a patch this small and simple, we minimally owe Pavel a direct
> answer about its rejection.
>

It's not necessary. But we did not go one step forward :(. The same
situation can be repeated next year.

so I would to see a Robert's patch, if it is possible. And can be nice
if this simple issue can be done with this commitfest.

I can do more performance test of my initial patch. Maybe this patch
isn't nice, but I am sure, so this version has a minimal negative
impact and maximal positive impact.

We speaking about twenty lines that can removed when people will
report a potential problems, so any variant - mine or Tom's can be
simply removed. It doesn't modify behave of executions, it doesn't
append a new feature. It just remove a one pathologic (+/-) issue.

I can live without this patch. I know workaround and know a symptoms.
It's pity so there isn't any PostGIS user (in this discus). For these
people it can be a implicit detoasting interesting and can help with
real tests.

Regards

Pavel

> Thanks,
> nm
>