Re: standby recovery fails (tablespace related) (tentative patch and discussion) - Mailing list pgsql-hackers

From Alvaro Herrera
Subject Re: standby recovery fails (tablespace related) (tentative patch and discussion)
Date
Msg-id 20220805202940.oneu7mlg67cpo5jd@alvherre.pgsql
Whole thread Raw
In response to Re: standby recovery fails (tablespace related) (tentative patch and discussion)  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
On 2022-Jul-30, Tom Lane wrote:

> BTW, quite aside from stability, is it really necessary for this test to
> be so freakin' slow?  florican for instance reports
> 
> [12:54:07] t/033_replay_tsp_drops.pl ............ ok   117840 ms ( 0.01 usr  0.00 sys +  8.72 cusr  5.41 csys = 14.14
CPU)
> 
> 027 is so bloated because it runs the core regression tests YA time,
> which I'm not very happy about either; but that's no excuse for
> every new test to contribute an additional couple of minutes.

Definitely not intended.  It looks like the reason is just that the DROP
DATABASE/TABLESPACE commands are super slow, and this test does a lot of
that.  I added some instrumentation and the largest fraction of time
goes to execute this

        CREATE DATABASE dropme_db1 WITH TABLESPACE dropme_ts1;
        CREATE TABLE t (a int) TABLESPACE dropme_ts2;
        CREATE DATABASE dropme_db2 WITH TABLESPACE dropme_ts2;
        CREATE DATABASE moveme_db TABLESPACE source_ts;
        ALTER DATABASE moveme_db SET TABLESPACE target_ts;
        CREATE DATABASE newdb TEMPLATE template_db;
        ALTER DATABASE template_db IS_TEMPLATE = false;
        DROP DATABASE dropme_db1;
        DROP TABLE t;
        DROP DATABASE dropme_db2;
        DROP TABLESPACE dropme_ts2;
        DROP TABLESPACE source_ts;
        DROP DATABASE template_db;

Maybe this is overkill and we can reduce the test without damaging the
coverage.  I'll have a look during the weekend.

I'll repair the reliability problem too, separately.

-- 
Álvaro Herrera        Breisgau, Deutschland  —  https://www.EnterpriseDB.com/
"This is a foot just waiting to be shot"                (Andrew Dunstan)



pgsql-hackers by date:

Previous
From: Nathan Bossart
Date:
Subject: Re: optimize lookups in snapshot [sub]xip arrays
Next
From: Andres Freund
Date:
Subject: Re: PG 15 (and to a smaller degree 14) regression due to ExprEvalStep size