pg_bench

# create the test database with the name "test"
psql -d postgres -U postgres -c "CREATE DATABASE test"

# -i = initialize 
# -s = scale default database value(16MB) * s
# time = measure the time for executing the command
pgbench -i -s 50 test -U postgres

# from pgbench created tables
#tablename              number of rows
--------------------------------------
pgbench_branches        s
pgbench_tellers         s*10
pgbench_accounts        s*100.000
pgbench_history         0

# c = number of client connections to simulate
# j = number of worker processes for pgbench
# t = tps per client session => c*t
pgbench -c 10 -j 2 -t 10000 test -U postgres

# read-only test
# create the test database with the name "test_read"
psql -d postgres -U postgres -c "CREATE DATABASE test_read"

# -S = use built in select only script
pgbench -h <Standby LoadBalancer IP> -p 5432 -d -c 50 -j 10 -t 10000 -S test_read -U postgres

# kill database with heavy resource usage
pgbench -c 90 -j 10 -t 100000 test -U postgres

# get size of database
SELECT pg_size_pretty( pg_database_size('databasename') );