addd postgresql settings for hopefully better performance

nextcloud/Containerfile

@@ -65,9 +65,14 @@ RUN mv php/php.ini /etc/php/${PHPV:?}/fpm/ && \
 ### PostgreSQL ###
 ###
 
-# configure PostgreSQL access
-COPY --chown=postgres:postgres assets/pg_hba.conf ./
-RUN mv pg_hba.conf /etc/postgresql/${PSQLV:?}/main/
+# configure PostgreSQL
+COPY --chown=postgres:postgres assets/postgresql ./
+# If the posgresql.conf file contains multiple entries for the same parameter, all but the last one is ignored.
+# So we can just append our settings to the already-existing postgresql.conf file.
+RUN mv postgresql/pg_hba.conf /etc/postgresql/${PSQLV:?}/main/ & \
+    cat postgresql/postgresql.conf >> /etc/postgresql/${PSQLV:?}/main/postgresql.conf
+
+
 
 ###
 ### Apache

nextcloud/assets/postgresql/postgresql.conf

@@ -0,0 +1,27 @@
+# The following configuration parameters were generated using the PGTune tool
+# https://pgtune.leopard.in.ua/
+# parameters:
+
+# DB Version: 13
+# OS Type: linux
+# DB Type: web
+# Total Memory (RAM): 16 GB
+# CPUs num: 6
+# Data Storage: ssd
+
+max_connections = 200
+shared_buffers = 4GB
+effective_cache_size = 12GB
+maintenance_work_mem = 1GB
+checkpoint_completion_target = 0.9
+wal_buffers = 16MB
+default_statistics_target = 100
+random_page_cost = 1.1
+effective_io_concurrency = 200
+work_mem = 6990kB
+min_wal_size = 1GB
+max_wal_size = 4GB
+max_worker_processes = 6
+max_parallel_workers_per_gather = 3
+max_parallel_workers = 6
+max_parallel_maintenance_workers = 3