Re: pg_upgrade failing for 200+ million Large Objects
Alexander Korotkov <aekorotkov@gmail.com>
From: Alexander Korotkov <aekorotkov@gmail.com>
To: Justin Pryzby <pryzby@telsasoft.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Nathan Bossart <nathandbossart@gmail.com>, Michael Banck <mbanck@gmx.net>, Laurenz Albe <laurenz.albe@cybertec.at>, vignesh C <vignesh21@gmail.com>, "Kumar, Sachin" <ssetiya@amazon.com>, Robins Tharakan <tharakan@gmail.com>, Jan Wieck <jan@wi3ck.info>,
Bruce Momjian <bruce@momjian.us>, Andrew Dunstan <andrew@dunslane.net>, Magnus Hagander <magnus@hagander.net>, Peter Eisentraut <peter.eisentraut@enterprisedb.com>,
pgsql-hackers@postgresql.org
Date: 2024-07-26T21:42:23Z
Lists: pgsql-hackers
On Fri, Jul 26, 2024 at 11:36 PM Justin Pryzby <pryzby@telsasoft.com> wrote:
> On Wed, Jul 24, 2024 at 09:17:51AM -0500, Justin Pryzby wrote:
> > With partitioning, we have a lot of tables, some of them wide (126
> > partitioned tables, 8942 childs, total 1019315 columns).
>
> On Fri, Jul 26, 2024 at 10:53:30PM +0300, Alexander Korotkov wrote:
> > It would be nice to identify such cases and check which memory contexts are
> > growing and why.
>
> I reproduced the problem with this schema:
>
> SELECT format('CREATE TABLE p(i int, %s) PARTITION BY RANGE(i)', array_to_string(a, ', ')) FROM (SELECT array_agg(format('i%s int', i))a FROM generate_series(1,999)i);
> SELECT format('CREATE TABLE t%s PARTITION OF p FOR VALUES FROM (%s)TO(%s)', i,i,i+1) FROM generate_series(1,999)i;
>
> This used over 4 GB of RAM.
> 3114201 pryzbyj 20 0 5924520 4.2g 32476 T 0.0 53.8 0:27.35 postgres: pryzbyj postgres [local] UPDATE
>
> The large context is:
> 2024-07-26 15:22:19.280 CDT [3114201] LOG: level: 1; CacheMemoryContext: 5211209088 total in 50067 blocks; 420688 free (14 chunks); 5210788400 used
>
> Note that there seemed to be no issue when I created 999 tables without
> partitioning:
>
> SELECT format('CREATE TABLE t%s(LIKE p)', i,i,i+1) FROM generate_series(1,999)i;
Thank you! That was quick.
I'm looking into this.
------
Regards,
Alexander Korotkov
Supabase
Commits
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the thread's linked commits as JSON, with link sources.
API reference →
-
Count individual SQL commands in pg_restore's --transaction-size mode.
- 81db073a2878 17.0 landed
- 0f1290521504 18.0 landed
-
Reduce number of commands dumpTableSchema emits for binary upgrade.
- b3f0e0503f33 18.0 landed
- 2fa989e6a340 17.0 landed
-
Invent --transaction-size option for pg_restore.
- 959b38d770ba 17.0 landed
-
Rearrange pg_dump's handling of large objects for better efficiency.
- a45c78e3284b 17.0 landed
-
Add temporal PRIMARY KEY and UNIQUE constraints
- 46a0cd4cefb4 17.0 cited
-
Fix typo and case in messages
- 7d7ef075d2b3 17.0 cited