Re: pgsql 10: hash indexes testing

Amit Kapila <amit.kapila16@gmail.com>

From: Amit Kapila <amit.kapila16@gmail.com>
To: AP <ap@zip.com.au>
Cc: Robert Haas <robertmhaas@gmail.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2017-08-14T01:47:35Z
Lists: pgsql-hackers
On Mon, Aug 14, 2017 at 6:10 AM, AP <ap@zip.com.au> wrote:
> On Fri, Aug 11, 2017 at 07:33:51AM +0530, Amit Kapila wrote:
>> On Thu, Aug 10, 2017 at 4:11 PM, AP <ap@zip.com.au> wrote:
>> > mdstash=# select * from pgstathashindex('link_datum_id_idx');
>> >  version | bucket_pages | overflow_pages | bitmap_pages | unused_pages | live_items | dead_items |   free_percent
>> > ---------+--------------+----------------+--------------+--------------+------------+------------+------------------
>> >        4 |     12391325 |        5148912 |          158 |       191643 | 4560007478 |          0 | 1894.29056075982
>> > (1 row)
>>
>> The free_percent calculation seems to be wrong.  Can you please once
>> try after recent commit 0b7ba3d6474b8f58e74dba548886df3250805cdf?  I
>> feel this should be fixed by that commit.
>
> Sorry I couldn't get to help you debugging this myself. Work got annoying. :/
>
> That said, I think that this is the first time that I've seen the value be
> under 100:
>

Thanks for confirming the same.

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


Commits

  1. pgstatindex: Insert some casts to prevent overflow.

  2. hash: Immediately after a bucket split, try to clean the old bucket.

  3. hash: Increase the number of possible overflow bitmaps by 8x.

  4. BRIN auto-summarization