On Tue, Jan 20, 2015 at 8:39 PM, Peter Geoghegan <pg@heroku.com> wrote:
> On Tue, Jan 20, 2015 at 5:32 PM, Robert Haas <robertmhaas@gmail.com> wrote:
>> I was assuming we were going to fix this by undoing the abbreviation
>> (as in the abort case) when we spill to disk, and not bothering with
>> it thereafter.
>
> The spill-to-disk case is at least as compelling at the internal sort
> case. The overhead of comparisons is much higher for tapesort.
First, we need to unbreak this. Then, we can look at optimizing it.
The latter task will require performance testing.
--
Robert Haas
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