Hm. Here is a log-log chart of those results (sorry for html mail). I'm not
really sure if log-log is the right tool to use for a O(nlog(n)) curve
I think the take-away is that this is outside the domain where any
interesting break points occur. Maybe run more tests on the low end to find
where the tapesort can generate a single tape and avoid the merge and see
where the discontinuity is with quicksort for the various work_mem sizes.
And can you calculate an estimate where the domain would be where multiple
passes would be needed for this table at these work_mem sizes? Is it
feasible to test around there?
[image: Inline image 1]