Horton

Re: Parallel Index Scans

Amit Kapila <amit.kapila16@gmail.com>

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From: Amit Kapila <amit.kapila16@gmail.com>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Anastasia Lubennikova <a.lubennikova@postgrespro.ru>, Anastasia Lubennikova <lubennikovaav@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>, Rahila Syed <rahilasyed.90@gmail.com>
Date: 2017-01-20T10:08:49Z
Lists: pgsql-hackers 
On Fri, Jan 20, 2017 at 12:59 AM, Robert Haas <robertmhaas@gmail.com> wrote:
> On Thu, Jan 19, 2017 at 4:26 AM, Amit Kapila <amit.kapila16@gmail.com> wrote:
>> Fixed.
>
>
> If all of that were no issue, the considerations in
> TargetListSupportsBackwardScan could be a problem, too.  But I think
> there shouldn't be any issue having Gather just continue to return
> false.
>

You are right.  I have added that code under the assumption that if
the underlying node (in this case index scan) can support backward
scan, gather can also support.  I forgot/missed that
ExecSupportsBackwardScan is to support cursors operations.  Will fix
in next version of patch.


-- 
With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com

Commits

  1. Replace min_parallel_relation_size with two new GUCs.

  2. Factor out logic for computing number of parallel workers.

  3. Support condition variables.

  4. Allow parallel custom and foreign scans.

  5. Add a C API for parallel heap scans.