Re: Parallel Seq Scan

> > a. Infrastructure for parallel execution, like some of the stuff in
> > execparallel.c, heapam.c,tqueue.c, etc and all other generic
> > (non-nodes specific) code.
> 
> Did you consider passing tuples through the tqueue by reference rather
> than copying? The page should be pinned by the worker process, but
> perhaps that's a bad assumption to make?
>
Is the upcoming PartialAggregate/FinalAggregate a solution for the problem?
More or less, the Funnel node run on single core has to process massive
amount of tuples that are fetched in parallel.

Thanks,
--
NEC Business Creation Division / PG-Strom Project
KaiGai Kohei <kaigai@ak.jp.nec.com>


> -----Original Message-----
> From: Jeff Davis [mailto:pgsql@j-davis.com]
> Sent: Wednesday, July 01, 2015 4:51 PM
> To: Amit Kapila
> Cc: Robert Haas; Haribabu Kommi; Andres Freund; Kaigai Kouhei(海外 浩平); Amit
> Langote; Amit Langote; Fabrízio Mello; Thom Brown; Stephen Frost; pgsql-hackers
> Subject: Re: [HACKERS] Parallel Seq Scan
> 
> On Wed, 2015-07-01 at 11:07 +0530, Amit Kapila wrote:
> 
> > For what you are asking to change name for?
> 
> There are still some places, at least in the comments, that call it a
> parallel sequential scan.
> 
> 
> > a. Infrastructure for parallel execution, like some of the stuff in
> > execparallel.c, heapam.c,tqueue.c, etc and all other generic
> > (non-nodes specific) code.
> 
> Did you consider passing tuples through the tqueue by reference rather
> than copying? The page should be pinned by the worker process, but
> perhaps that's a bad assumption to make?
> 
> Regards,
>     Jeff Davis
>