Re: GEQO threshold results

You asked me to re-do the tests I had run to check the GEQO
threshold. With today's sources I get these runtimes:

# Tables: 7 8 9 10 11

std, with indexes 1.89 2.26 5.41 24.21 90.04
GEQO, with indexes 3.73 6.98 16.98 43.81* 21.45
std, no indexes 1.60 1.79 4.78 15.75 84.17
GEQO, no indexes 3.30 6.04 15.52 18.73 22.35

So, (a) the number of indexes is still not very relevant,
and (b) it looks like we oughta kick over to GEQO at 11 tables.

WHat were we at before? 6 or 8 I think? Nice job :-)

regards, tom lane

* That number is obviously out of line ... probably it was
skewed by some other activity on my system at the time.
I'm too lazy to repeat the measurement however.

Done. Thanks for doing the checking.

Doesn't seem like much of an increase, but it is N!, so I guess it is:

6!

720

8!

40320

11!

39916800

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