Re: Locking B-tree leafs immediately in exclusive mode

Alexander Korotkov <a.korotkov@postgrespro.ru>

From: Alexander Korotkov <a.korotkov@postgrespro.ru>
To: yoshikazu_i443@live.jp
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2018-07-25T12:20:59Z
Lists: pgsql-hackers
Hi!

On Tue, Jul 10, 2018 at 4:39 PM 今井 良一 <yoshikazu_i443@live.jp> wrote:
> On 2018/07/10 20:36, Alexander Korotkov wrote:
> > Thank you for the experiments!  It seems that there is real regression
> > here...  BTW, which script were you using in this benchmark:
> > script_unordered.sql or script_duplicated.sql?
>
> Sorry, I forgot to write that. I used script_unordered.sql.

I've reread the thread.  And I found that in my initial letter [1] I
forget to include index definition.
CREATE INDEX unordered_i_idx ON unordered (i);

So, when you did experiments [2], did you define any index on
unordered table?  If not, then it's curious why there is any
performance difference at all.

1. https://www.postgresql.org/message-id/CAPpHfduAMDFMNYTCN7VMBsFg_hsf0GqiqXnt%2BbSeaJworwFoig%40mail.gmail.com
2. https://www.postgresql.org/message-id/0F97FA9ABBDBE54F91744A9B37151A51189451%40g01jpexmbkw24

------
Alexander Korotkov
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company


Commits

  1. Reduce path length for locking leaf B-tree pages during insertion