On Tue, May 15, 2018 at 2:11 AM, Bruce Momjian <bruce@momjian.us> wrote:
> On Mon, May 14, 2018 at 05:34:54PM +0530, Dilip Kumar wrote:
>>
>> On Fri, May 11, 2018 at 8:38 PM, Bruce Momjian <bruce@momjian.us> wrote:
>>
>> I have committed the first draft of the Postgres 11 release notes. I
>> will add more markup soon. You can view the most current version here:
>>
>> http://momjian.us/pgsql_docs/release-11.html
>>
>> I expect a torrent of feedback. ;-)
>>
>> On a personal note, I want to apologize for not adequately championing
>> two features that I think have strategic significance but didn't make it
>> into Postgres 11: parallel FDW access and improved multi-variate
>> statistics. I hope to do better job during Postgres 12.
>>
>> --
>> Bruce Momjian <bruce@momjian.us> http://momjian.us
>> EnterpriseDB http://enterprisedb.com
>>
>> + As you are, so once was I. As I am, so you will be. +
>> + Ancient Roman grave inscription +
>>
>>
>>
>> I think the below commit is missed in the release notes?
>>
>> 5edc63bda68a77c4d38f0cbeae1c4271f9ef4100
>>
>> Committer: Robert Haas <rhaas@postgresql.org> 2017-11-10 13:50:50
>>
>> Account for the effect of lossy pages when costing bitmap scans.
>>
>> Dilip Kumar, reviewed by Alexander Kumenkov, Amul Sul, and me.
>> Some final adjustments by me.
>>
>> As part of this commit, we are also accounting for the lossy pages during
>> bitmap costing. This will consider
>> the effect of work_mem while selecting the bitmap heap scan path.
>
> Uh, that seems very exotic to mention, sorry. Others have opinions?
>
This patch improves the plan selection in many cases, see the
discussion of this patch[1][2]. The change in plan leads to
significant performance improvements in a number of TPC-H queries at
various settings. I think it is worth considering to add this in the
release notes.
[1] - https://www.postgresql.org/message-id/CAFiTN-uL%3DrQtvt9zFnLV9khXODhEyJTvC4TB135HSK1%3DYdFAxQ%40mail.gmail.com
[2] - https://www.postgresql.org/message-id/9daaf288-e67f-f349-965f-3a8c6e0819ae%40postgrespro.ru
--
With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com
