Re: pgsql: Parameter toast_tuple_target controls TOAST for new rows

On 19 November 2017 at 19:49, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Andres Freund <andres(at)anarazel(dot)de> writes:
>> On 2017-11-19 19:08:48 -0500, Simon Riggs wrote:
>>> Am investigating the few buildfarm failures
>
>> The tests look very sensitive to differences in tuple size due to
>> different alignment requirements. Dependant on what MAXALIGN (and some
>> others) is the number of tuples fitting on a page will differ.
>
> "Few" buildfarm failures? It's probably going to fail on every 32-bit host.
>
> TBH, I would just remove those test cases. Even if they were stable
> across platforms, they don't directly prove anything at all about
> whether the feature does what it's supposed to.
>
> (Also, scaling the results to blocksize seems unlikely to help in
> passing on different BLCKSZ configurations...)

I just committed a change while this email arrived. I think what I've
done is essentially this.

The original test was more about demonstrating effectiveness.

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