Tom Lane wrote:
> CVSROOT:      /cvsroot
> Module name:  pgsql-server
> Changes by:   [EMAIL PROTECTED]       04/03/17 18:24:58
> 
> Modified files:
>       src/backend/utils/sort: tuplesort.c 
> 
> Log message:
>       During btree index build, sort equal-keyed tuples according to their
>       TID (heap position).  This doesn't do anything to the validity of the
>       finished index, but by pretending to qsort() that there are no really
>       equal keys in the sort, we can avoid performance problems with qsort
>       implementations that have trouble with large numbers of equal keys.
>       Patch from Manfred Koizar.

I think there is also the advantage that many equal keys will access the
heap in a more sequential, rather than random, order, which is the part
that really excited me.

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  [EMAIL PROTECTED]               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

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