On Tue, Mar 28, 2017 at 5:27 PM, David Steele <da...@pgmasters.net> wrote:
> Hi Alexander, > > On 3/20/17 10:19 AM, Heikki Linnakangas wrote: > >> On 03/20/2017 11:33 AM, Alexander Korotkov wrote: >> >>> Please, find rebased patch in the attachment. >>> >> >> I had a quick look at this. >> > > <...> > > According to 'perf', 85% of the CPU time is spent in ExecCopySlot(). To >> alleviate that, it might be worthwhile to add a special case for when >> the group contains exactly one group, and not put the tuple to the >> tuplesort in that case. Or if we cannot ensure that the Incremental Sort >> is actually faster, the cost model should probably be smarter, to avoid >> picking an incremental sort when it's not a win. >> > > This thread has been idle for over a week. Please respond with a new > patch by 2017-03-30 00:00 AoE (UTC-12) or this submission will be marked > "Returned with Feedback". Thank you for reminder! ------ Alexander Korotkov Postgres Professional: http://www.postgrespro.com The Russian Postgres Company
