On Sat, Jan 18, 2014 at 7:22 PM, Marti Raudsepp <marti@juffo.org> wrote:
> Total runtime: 5.418 ms
Oops, shouldn't have rushed this. Clearly the timings should have
tipped me off that it's broken. I didn't notice that cmpSortSkipCols
was re-using tuplesort's sortkeys.
Here's a patch that actually works; I added a new skipKeys attribute
to SortState. I had to extract the SortSupport-creation code from
tuplesort_begin_heap to a new function; but that's fine, because it
was already duplicated in ExecInitMergeAppend too.
I reverted the addition of tuplesort_get_sortkeys, which is not needed now.
Now the timings are:
Unpatched partial sort: 13478.158 ms
Full sort: 6802.063 ms
Patched partial sort: 6618.962 ms
Regards,
Marti
