# DISCLAIMER - Software and the resulting config files are provided "AS IS" - IN NO EVENT SHALL
# BE THE CREATOR LIABLE TO ANY PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL
# DAMAGES, INCLUDING LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION.

# Connectivity
max_connections = 500
superuser_reserved_connections = 3

# Memory Settings
shared_buffers = '8192 MB'
work_mem = '64 MB'
maintenance_work_mem = '420 MB'
huge_pages = try   # NB! requires also activation of huge pages via kernel params, see here for more:
                   # https://www.postgresql.org/docs/current/static/kernel-resources.html#LINUX-HUGE-PAGES
effective_cache_size = '22 GB'
effective_io_concurrency = 300   # concurrent IO only really activated if OS supports posix_fadvise function

# Monitoring
shared_preload_libraries = 'pg_stat_statements'    # per statement resource usage stats
track_io_timing=on        # measure exact block IO times
track_functions=pl        # track execution times of pl-language procedures if any

# Replication
wal_level = replica     # consider using at least 'replica'
max_wal_senders = 0
synchronous_commit = off
wal_keep_segments = 130

# Checkpointing:
checkpoint_timeout  = '15 min'
checkpoint_completion_target = 0.9
max_wal_size = '1024 MB'
min_wal_size = '512 MB'


# WAL writing
wal_compression = on
wal_buffers = -1    # auto-tuned by Postgres till maximum of segment size (16MB by default)

# Background writer
bgwriter_delay = 200ms
bgwriter_lru_maxpages = 100
bgwriter_lru_multiplier = 2.0
bgwriter_flush_after = 0

# Parallel queries:
max_worker_processes = 24
max_parallel_workers_per_gather = 12
max_parallel_maintenance_workers = 12
max_parallel_workers = 24
parallel_leader_participation = on

# Advanced features

enable_partitionwise_join = on
enable_partitionwise_aggregate = on

# General notes:
# We recommend not to use read-only replicas for scaling
# Note that not all settings are automatically tuned.
#   Consider contacting experts at
#   https://www.cybertec-postgresql.com
#   for more professional expertise.