On 2018-Jun-24, Peter Geoghegan wrote:
> nbtsort.c has a comment block from the Berkeley days that reads:
>
> * This code is moderately slow (~10% slower) compared to the regular
> * btree (insertion) build code on sorted or well-clustered data. On
> * random data, however, the insertion build code is unusable -- the
> * difference on a 60MB heap is a factor of 15 because the random
> * probes into the btree thrash the buffer pool. (NOTE: the above
> * "10%" estimate is probably obsolete, since it refers to an old and
> * not very good external sort implementation that used to exist in
> * this module. tuplesort.c is almost certainly faster.)
>
> I propose removing this whole comment block (patch attached),
Makes sense to me, +1.
--
Álvaro Herrera https://www.2ndQuadrant.com/
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