Re: Poor memory context performance in large hash joins

On Thu, Feb 23, 2017 at 2:13 PM, Jeff Janes <jeff.janes@gmail.com> wrote:
> Is there a good solution to this?  Could the new chunks be put in a
> different memory context, and then destroy the old context and install the
> new one at the end of ExecHashIncreaseNumBatches? I couldn't find a destroy
> method for memory contexts, it looks like you just reset the parent instead.
> But I don't think that would work here.

Are you aware of the fact that tuplesort.c got a second memory context
for 9.6, entirely on performance grounds?


-- 
Peter Geoghegan