Hi Andres:
Could you please share your thoughts on QUERY 3?
The performance impact of this regression increases *linearly* on larger
databases. We concur with Andrew in that this is related to the lack of a
Materialize node and mis-costing of the Nested Loop Anti-Join.
We found more than 20 r
16, 2019 5:37:49 PM
To: Andres Freund
Cc: Jung, Jinho; Jeff Janes; pgsql-performa...@postgresql.org
Subject: Re: Performance regressions found using sqlfuzz
Andres Freund writes:
> On 2019-02-14 17:27:40 +, Jung, Jinho wrote:
>> - Our analysis: We believe that this regression has to
Andres Freund writes:
> On 2019-02-14 17:27:40 +, Jung, Jinho wrote:
>> - Our analysis: We believe that this regression has to do with two factors:
>> 1) conditional expression (e.g., LEAST or NULLIF) are not reduced to
>> constants unlike string functions (e.g., CHAR_LENGTH) 2) change in t
Hi,
On 2019-02-14 17:27:40 +, Jung, Jinho wrote:
> ### QUERY 2:
>
> select distinct
> ref_0.i_im_id as c0,
> ref_1.ol_dist_info as c1
> from
> public.item as ref_0 right join
> public.order_line as ref_1
> on (ref_0.i_id = 5)
>
> - Commit: 84f9a35 (Improve e
> "Jung" == Jung, Jinho writes:
Jung> select distinct
Jung> ref_0.i_im_id as c0,
Jung> ref_1.ol_dist_info as c1
Jung> from
Jung> public.item as ref_0 right join
Jung> public.order_line as ref_1
Jung> on (ref_0.i_id = 5)
Jung> - Commit: 84f9a35 (Improve e
th=20) (actual
time=0.000..0.000 rows=0 loops=30044)
One-Time Filter: false
Planning Time: 0.350 ms
Execution Time: 79.237 ms
From: Jeff Janes
Sent: Tuesday, February 12, 2019 1:03 PM
To: Jung, Jinho
Cc: pgsql-performa...@postgresql.org
On Tue, Feb 12, 2019 at 4:23 AM Jung, Jinho wrote:
>
> Hello,
>
> We are developing a tool called sqlfuzz for automatically finding
> performance regressions in PostgreSQL. sqlfuzz performs mutational fuzzing
> to generate SQL queries that take more time to execute on the latest
> version of Post
Re: Jung, Jinho 2019-02-11
> We are developing a tool called sqlfuzz for automatically finding performance
> regressions in PostgreSQL. sqlfuzz performs mutational fuzzing to generate
> SQL queries that take more time to execute on the latest version of
> PostgreSQL compared to prior versions.
