Re: [PERFORM] A Better External Sort?

Martijn van Oosterhout <kleptog@svana.org> writes:
> Anyway, to bring some real info I just profiled PostgreSQL 8.1beta
> doing an index create on a 2960296 row table (3 columns, table size
> 317MB).

3 columns in the index you mean?  What were the column datatypes?
Any null values?

> The number 1 bottleneck with 41% of user time is comparetup_index.
> ...
> The thing is, I can't see anything in comparetup_index() that could
> take much time.

The index_getattr and heap_getattr macros can be annoyingly expensive.
        regards, tom lane