PG throws could not resize shared memory segment error

Installation
3

This is due to the fact that docker by default restricts shared memory size to 64MB which makes pg10 run afoul of this limitation when doing a number of scatter/gather jobs in parallel:

Outside the container:
supermathie@host: ~ $ df -h /dev/shm
Filesystem      Size  Used Avail Use% Mounted on
none             63G  1.2M   63G   1% /run/shm

Inside the container:
supermathie@host: ~ $ docker exec -it postgres-master df -h /dev/shm
Filesystem      Size  Used Avail Use% Mounted on
shm              64M  8.0K   64M   1% /dev/shm

You should raise the limit when launching the postgres container by including the --shm-size=1g parameter.

We’ll look at fixing this in the launcher.

(or as the link suggests, disable parallelism in pg10 with max_parallel_workers_per_gather = 0)

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