Re: BUG #14722: Segfault in tuplesort_heap_siftup, 32 bit overflow

On Thu, 2017-06-29 at 11:59 -0700, Peter Geoghegan wrote:
> On Thu, Jun 29, 2017 at 9:16 AM, <skoposov(at)cmu(dot)edu> wrote:
> > Here are the commands leading to the crash:
> >
> > wsdb=# set maintenance_work_mem to '70GB';
> >
> > SET
> > wsdb=# create index on cgonzal.vvv_single_ks_sorted (q3c_ang2ipix(ra,dec));
> >
> >
> > ----
> >
> > Importantly the table has already been sorted by q3c_ang2ipix(ra,dec) !
>
> BTW, given the exact details of what you're doing here, using only 1MB
> of maintenance_work_mem will probably make the operation complete
> sooner.
>
>

Thank you. It does seem to be ~ 50% faster.
It is somewhat unfortunate that maintenance_work_mem is
counterproductive in this scenario, given that indexing an ordered table
is a natural step in clustering a table...

Sergey