We occasionally run into an internal error when creating tables. The error message is «could not create file "base/17006/2851173576": File exists» with SQLSTATE 58P02. The attachment is included with this email contains the PostgreSQL logs. Note that some identifiers are renamed in the logs because they contain sensitive information, but identifier names are unlikely the source of the error.
An old mailing list thread [1] suggests a problem related to OID wraparound. Our use case involves creating and dropping thousands of tables every day. The CREATE TABLE statements for these tables are similar to the one in the attached logs, but with different table names and columns. Nonetheless, the error is difficult to reproduce as it happens only sporadically. Retrying the CREATE TABLE statement fixes the problem temporarily.
Some more information about our PostgreSQL instance and usage:
PostgreSQL version: PostgreSQL 10.6 (Ubuntu 10.6-1.pgdg16.04+1) on x86_64-pc-linux-gnu, compiled by gcc (Ubuntu 5.4.0-6ubuntu1~16.04.10) 5.4.0 20160609, 64-bit.
The DBMS did not crash or abruptly shut down recently.
The file base/17006/2851173576 was actually in use by an index, as indicated by pg_class.relfilenode.
Autovacuum is disabled for these tables. Logging is disabled for these tables upon creation, but enabled after filling them with data.
The query “SELECT max(oid) FROM pg_class” reports 4,294,603,797, which is close to 2³² - 1.
