# PostgreSQL Configuration for Foxhunt HFT Trading System
# Optimized for high-performance trading workloads

#============================================================================
# CONNECTION SETTINGS
#============================================================================
listen_addresses = '*'
port = 5432
max_connections = 200
superuser_reserved_connections = 3

#============================================================================
# RESOURCE USAGE
#============================================================================
shared_buffers = 256MB                # 25% of available RAM (1GB container)
huge_pages = try
temp_buffers = 8MB
max_prepared_transactions = 200
work_mem = 4MB
maintenance_work_mem = 64MB
autovacuum_work_mem = -1
max_stack_depth = 2MB
dynamic_shared_memory_type = posix

#============================================================================
# WRITE AHEAD LOG (WAL) - Critical for HFT performance
#============================================================================
wal_level = replica
fsync = on
synchronous_commit = on
wal_sync_method = fdatasync
full_page_writes = on
wal_compression = on
wal_buffers = 16MB
wal_writer_delay = 200ms
commit_delay = 0
commit_siblings = 5

# Checkpoints - Balance between performance and recovery
checkpoint_segments = 32              # PostgreSQL < 9.5
max_wal_size = 1GB                   # PostgreSQL >= 9.5
min_wal_size = 80MB
checkpoint_completion_target = 0.9
checkpoint_timeout = 5min
checkpoint_warning = 30s

#============================================================================
# ARCHIVING - For point-in-time recovery
#============================================================================
archive_mode = on
archive_command = 'cp %p /var/lib/postgresql/archive/%f'
archive_timeout = 0

#============================================================================
# REPLICATION - For high availability
#============================================================================
max_wal_senders = 3
wal_keep_segments = 100              # PostgreSQL < 13
wal_keep_size = 1GB                  # PostgreSQL >= 13
hot_standby = on
hot_standby_feedback = off

#============================================================================
# QUERY TUNING
#============================================================================
random_page_cost = 1.1               # For SSD storage
seq_page_cost = 1.0
cpu_tuple_cost = 0.01
cpu_index_tuple_cost = 0.005
cpu_operator_cost = 0.0025
effective_cache_size = 1GB           # Available OS cache
default_statistics_target = 100

#============================================================================
# PLANNER SETTINGS
#============================================================================
enable_hashagg = on
enable_hashjoin = on
enable_indexscan = on
enable_indexonlyscan = on
enable_material = on
enable_mergejoin = on
enable_nestloop = on
enable_seqscan = on
enable_sort = on
enable_tidscan = on

#============================================================================
# ERROR REPORTING AND LOGGING
#============================================================================
log_destination = 'stderr'
logging_collector = off              # Docker handles logging
log_directory = '/var/log/postgresql'
log_filename = 'postgresql-%Y-%m-%d_%H%M%S.log'
log_file_mode = 0600
log_truncate_on_rotation = off
log_rotation_age = 1d
log_rotation_size = 100MB

# What to log
log_min_messages = warning
log_min_error_statement = error
log_min_duration_statement = 1000    # Log queries longer than 1 second
log_checkpoints = on
log_connections = on
log_disconnections = on
log_lock_waits = on
log_statement = 'none'               # 'all' for debugging
log_temp_files = 10MB
log_timezone = 'UTC'

#============================================================================
# RUNTIME STATISTICS
#============================================================================
track_activities = on
track_counts = on
track_io_timing = on
track_functions = none
track_activity_query_size = 1024
stats_temp_directory = '/var/run/postgresql/stats_temp'

# Shared preload libraries
shared_preload_libraries = 'pg_stat_statements'

#============================================================================
# AUTOVACUUM - Critical for maintaining performance
#============================================================================
autovacuum = on
log_autovacuum_min_duration = 0
autovacuum_max_workers = 3
autovacuum_naptime = 1min
autovacuum_vacuum_threshold = 50
autovacuum_analyze_threshold = 50
autovacuum_vacuum_scale_factor = 0.2
autovacuum_analyze_scale_factor = 0.1
autovacuum_freeze_max_age = 200000000
autovacuum_multixact_freeze_max_age = 400000000
autovacuum_vacuum_cost_delay = 20ms
autovacuum_vacuum_cost_limit = -1

#============================================================================
# CLIENT CONNECTION DEFAULTS
#============================================================================
search_path = '"$user", public'
default_tablespace = ''
temp_tablespaces = ''
check_function_bodies = on
default_transaction_isolation = 'read committed'
default_transaction_read_only = off
default_transaction_deferrable = off
session_replication_role = 'origin'
statement_timeout = 0
lock_timeout = 0
idle_in_transaction_session_timeout = 0
vacuum_freeze_min_age = 50000000
vacuum_freeze_table_age = 150000000
vacuum_multixact_freeze_min_age = 5000000
vacuum_multixact_freeze_table_age = 150000000
bytea_output = 'hex'
xmlbinary = 'base64'
xmloption = 'content'
gin_fuzzy_search_limit = 0
gin_pending_list_limit = 4MB

#============================================================================
# LOCALE AND FORMATTING
#============================================================================
datestyle = 'iso, mdy'
intervalstyle = 'postgres'
timezone = 'UTC'
timezone_abbreviations = 'Default'
extra_float_digits = 0
client_encoding = 'UTF8'
lc_messages = 'en_US.utf8'
lc_monetary = 'en_US.utf8'
lc_numeric = 'en_US.utf8'
lc_time = 'en_US.utf8'

#============================================================================
# CUSTOM SETTINGS FOR HFT
#============================================================================
# Optimize for trading workloads
join_collapse_limit = 8
from_collapse_limit = 8
geqo = on
geqo_threshold = 12
geqo_effort = 5
geqo_pool_size = 0
geqo_generations = 0
geqo_selection_bias = 2.0
geqo_seed = 0.0

# Background writer tuning
bgwriter_delay = 200ms
bgwriter_lru_maxpages = 100
bgwriter_lru_multiplier = 2.0
bgwriter_flush_after = 512kB

# WAL writer tuning
wal_writer_flush_after = 1MB

# Synchronous replication (if using streaming replication)
synchronous_standby_names = ''

# Parallel query settings
max_parallel_workers_per_gather = 2
max_parallel_workers = 8
parallel_tuple_cost = 0.1
parallel_setup_cost = 1000.0
min_parallel_table_scan_size = 8MB
min_parallel_index_scan_size = 512kB