Date: Thu, 17 Oct 2019 05:14:25 -0300
From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Pg Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: parallel restore sometimes fails for FKs to partitioned tables
Message-ID: <20191017081425.GA18878@alvherre.pgsql>
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On 2019-Oct-05, Alvaro Herrera wrote:

> While playing around I noticed that depending on the number of parallel
> workers in pg_restore compared to the number of partitions a table has,
> restoring an FK fails because the FK itself is restored before the index
> partitions have completed restoring.  The exact conditions to cause the
> failure seem to vary depending on whether the dump is schema-only or not.
> 
> This can seemingly be fixed by having pg_dump make the constraint depend
> on the attach of each partition, as in the attached patch.  With this
> patch I no longer see failures.

Pushed with some additional tweaks.

Parallel restore of partitioned tables containing data and unique keys
still fails with some deadlock errors, though :-(

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services