Don't know if this is a bug or just undocumented, but it seems as you should turn off autovacuum before you run CLUSTER, otherwise you might run into a deadlock:

NOTICE: Clustering idx_vehicle_unit_data_200407_person_information__i d on vehicle_unit_data_200407
ERROR: deadlock detected
DETAIL: Process 29022 waits for AccessExclusiveLock on relation 68950 of database 16390; blocked by process 15865.
Process 15865 waits for AccessShareLock on relation 68122 of database 16390; blocked by process 29022.

/Mikael

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"Mikael Carneholm" <Mikael.Carneholm@WirelessCar.com> writes:
> Don't know if this is a bug or just undocumented, but it seems as you should turn off autovacuum before you run CLUSTER, otherwise you might run into a deadlock:

Which variant of CLUSTER were you using? ISTR that some of them lock
the index before the table, which is prone to deadlock against nearly
all other operations on the table (not just vacuum).

regards, tom lane

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