Hello,
Thanks for the feedback so far! Continue with the previous report, we
sharing another four interesting cases that SQLFuzz discovered.
(previous discussion:
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
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
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
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.o
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
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
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 PostgreSQL
compared to prior versions. We hope that these queries
