From: Tom Lane <tgl@sss.pgh.pa.us>
To: James Pang (chaolpan) <chaolpan@cisco.com>
Cc: pgsql-admin@lists.postgresql.org <pgsql-admin@lists.postgresql.org>
Subject: Re: multiple sessions to create index in parallel support
Date: Tue, 21 Jun 2022 10:30:01 -0400
Message-ID: <2944693.1655821801@sss.pgh.pa.us> (raw)
In-Reply-To: <PH0PR11MB5191540CA8085CAA8944A114D6B39@PH0PR11MB5191.namprd11.prod.outlook.com>
References: <PH0PR11MB5191540CA8085CAA8944A114D6B39@PH0PR11MB5191.namprd11.prod.outlook.com>
"James Pang (chaolpan)" <chaolpan@cisco.com> writes:
> We have a large database that just migrated data from Oracle to Postgres(13.4), after data load. We try to create indexes , with only one connection , the create index automatically run in parallel (table size 40G) , then we started two connections and each session creating index on large table, but at this time, only 1 session parallel creating index, the other one creating index in serial. There are enough parallel_workers and memory. Is that expected ? only 1 session allowed to parallel index creating at the same time ?
Check your settings for max_parallel_workers and
max_parallel_maintenance_workers.
regards, tom lane
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To: pgsql-admin@postgresql.org
Cc: tgl@sss.pgh.pa.us, chaolpan@cisco.com, pgsql-admin@lists.postgresql.org
Subject: Re: multiple sessions to create index in parallel support
In-Reply-To: <2944693.1655821801@sss.pgh.pa.us>
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