From: | Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> |
---|---|
To: | Anastasia Lubennikova <a(dot)lubennikova(at)postgrespro(dot)ru> |
Cc: | Anastasia Lubennikova <lubennikovaav(at)gmail(dot)com>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>, Rahila Syed <rahilasyed(dot)90(at)gmail(dot)com> |
Subject: | Re: Parallel Index Scans |
Date: | 2017-01-15 04:11:38 |
Message-ID: | CAA4eK1+v4EYh2+hkt5VNVX5TDkxjNuQ21jTs+yy3ifKFSRkP5A@mail.gmail.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
On Fri, Jan 13, 2017 at 7:58 PM, Anastasia Lubennikova
<a(dot)lubennikova(at)postgrespro(dot)ru> wrote:
> 27.12.2016 17:33, Amit Kapila:
>
>
> The similar problem has occurred while testing "parallel index only
> scan" patch and Rafia has included the fix in her patch [1] which
> ideally should be included in this patch, so I have copied the fix
> from her patch. Apart from that, I observed that similar problem can
> happen for backward scans, so fixed the same as well.
>
>
> I confirm that this problem is solved.
>
> But I'm trying to find the worst cases for this feature. And I suppose we
> should test parallel index scans with
> concurrent insertions. More parallel readers we have, higher the
> concurrency.
> I doubt that it can significantly decrease performance, because number of
> parallel readers is not that big,
>
> I am not sure if such a test is meaningful for this patch because
> parallelism is generally used for large data reads and in such cases
> there are generally not many concurrent writes.
>
>
> I didn't find any case of noticeable performance degradation,
> so set status to "Ready for committer".
>
Thank you for the review!
--
With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com
From | Date | Subject | |
---|---|---|---|
Next Message | Michael Paquier | 2017-01-15 05:44:33 | Re: Support for pg_receivexlog --format=plain|tar |
Previous Message | Tom Lane | 2017-01-14 21:18:49 | Re: BUG: pg_stat_statements query normalization issues with combined queries |