This is the default example configuration of 30-postgresql-shm.conf provided by PostgreSQL. This config file was generated by PostgreSQL running on Ubuntu 16.04.
It is located under: /etc/sysctl.d/30-postgresql-shm.conf
# Shared memory settings for PostgreSQL on Linux
# The settings here are upper limits; performance is not affected if the
# settings are larger than necessary. If other programs use shared memory as
# well, you will have to coordinate the size settings between them.
# Maximum size of a single shared memory segment in bytes
#kernel.shmmax = 33554432
# Maximum total size of all shared memory segments in pages (normally 4096 bytes)
#kernel.shmall = 2097152
Download the raw file with wget or curl
wget -O 30-postgresql-shm.conf.example http://exampleconfig.com/static/raw/postgresql/ubuntu16.04/etc/sysctl.d/30-postgresql-shm.conf
curl http://exampleconfig.com/static/raw/postgresql/ubuntu16.04/etc/sysctl.d/30-postgresql-shm.conf > 30-postgresql-shm.conf.example
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