Re: Parallel tuplesort (for parallel B-Tree index creation) - Mailing list pgsql-hackers

From Peter Geoghegan
Subject Re: Parallel tuplesort (for parallel B-Tree index creation)
Date
Msg-id CAM3SWZQ0EgCxs2NoEUwB6BACi-pp5qVmp432i+Wh_XyUrg1FbQ@mail.gmail.com
Whole thread Raw
In response to Re: Parallel tuplesort (for parallel B-Tree index creation)  (Peter Geoghegan <pg@heroku.com>)
Responses Re: Parallel tuplesort (for parallel B-Tree index creation)
List pgsql-hackers
On Mon, Nov 7, 2016 at 8:28 PM, Peter Geoghegan <pg@heroku.com> wrote:
> What do we need to teach pg_restore about parallel CREATE INDEX, if
> anything at all? Could this be as simple as a blanket disabling of
> parallelism for CREATE INDEX from pg_restore? Or, does it need to be
> more sophisticated than that? I suppose that tools like reindexdb and
> pgbench must be considered in a similar way.

I still haven't resolved this question, which seems like the most
important outstanding question, but I attach V6. Changes:

* tuplesort.c was adapted to use the recently committed condition
variables stuff. This made things cleaner. No more ad-hoc WaitLatch()
looping.

* Adapted docs to mention the newly committed max_parallel_workers GUC
in the context of discussing proposed max_parallel_workers_maintenance
GUC.

* Fixed trivial assertion failure bug that could be tripped when a
conventional sort uses very little memory.

--
Peter Geoghegan

Attachment

pgsql-hackers by date:

Previous
From: Peter Eisentraut
Date:
Subject: Re: [COMMITTERS] pgsql: Use latch instead of select() in walreceiver
Next
From: Alvaro Herrera
Date:
Subject: Re: Parallel tuplesort (for parallel B-Tree index creation)