Technical Tip: How to fix 'Error PSQLException: ERROR: no shared memory available'

This error occurs when queries are causing postgresql to run out of shared memory:

Error: "Error PSQLException: ERROR: no shared memory available
Tip: You may need to increase max_locks_per_transaction."

As the message indicates, the value of 'max_locks_per_transaction' has to be increased. In the case below, it will be increased to 200, but in other cases, it can be increased to 1024.

• Backup /cmdb/data/postgresql.conf file:

cp -rp /cmdb/data/postgresql.conf /cmdb/data/postgresql.conf.orig

Change the value of #max_locks_per_transaction:

vi /cmdb/data/postgresql.conf

From: # max_locks_per_transaction = 64 # min 10
to: max_locks_per_transaction = 200 # min 10

• Save the changes and exit.
• Restart postgresql-13 service:

systemctl stop postgresql-13
systemctl start postgresql-13

• Clear the cache and restart the Appserver:

su admin
cd /opt/phoenix/cache/
mv <Super_IP_dir> <Super_IP_dir>_old => example mv 10.0.0.1 10.0.0.1_old

cd /opt/glassfish/domains/domain1/
rm -rf generated/
rm -rf osgi-cache/
killall -9 java

Wait for 5-10 minutes and check the phProesses rate up with the 'phstatus' command.