On Mon, Jun 20, 2022 at 2:42 AM Fabio Pardi <f.pardi@portavita.eu> wrote:
> Is this behavior expected? I cannot find mentions on the documentation nor on the literature available to me.
Yes, this is expected. Parallel CREATE INDEX performs its parallel
sort by having workers generate sorted runs, which are written to temp
files, and then having the leader process merge the sorted runs
together as the index is built.
In the case where there is amble maintenance_work_mem, all writes to
and reads from temp files will be sequential.
--
Peter Geoghegan