# Foxhunt HFT Backtesting Service - Strategy Testing Engine
# Production SystemD unit for independent strategy backtesting
#
# INSTALLATION:
# 1. Ensure service user exists: sudo useradd -r -s /bin/false foxhunt
# 2. Copy to: sudo cp foxhunt-backtesting.service /etc/systemd/system/
# 3. Set permissions: sudo chmod 644 /etc/systemd/system/foxhunt-backtesting.service
# 4. Reload systemd: sudo systemctl daemon-reload
# 5. Enable service: sudo systemctl enable foxhunt-backtesting.service
#
# MANAGEMENT:
# - Start: sudo systemctl start foxhunt-backtesting
# - Stop: sudo systemctl stop foxhunt-backtesting
# - Status: sudo systemctl status foxhunt-backtesting
# - Logs: sudo journalctl -u foxhunt-backtesting -f

[Unit]
Description=Foxhunt HFT Backtesting Service
Documentation=https://github.com/foxhunt/foxhunt
After=network-online.target postgresql.service
Wants=network-online.target
Requires=postgresql.service

# Service dependencies  
Before=foxhunt-tli.service
PartOf=foxhunt.target

[Service]
Type=exec
ExecStart=/opt/foxhunt/bin/backtesting_service
ExecReload=/bin/kill -HUP $MAINPID
ExecStop=/bin/kill -TERM $MAINPID

# User and security
User=foxhunt
Group=foxhunt
DynamicUser=false

# Working directory and environment
WorkingDirectory=/opt/foxhunt
Environment=DATABASE_URL=postgresql://foxhunt:@localhost/foxhunt
Environment=RUST_LOG=info
Environment=RUST_BACKTRACE=1

# Performance optimizations
# CPU affinity - cores 2-3 to avoid interference with trading
CPUAffinity=2 3
Nice=0
IOSchedulingClass=2
IOSchedulingPriority=7

# Memory and resource limits
MemoryMax=4G
LimitNOFILE=65536
LimitNPROC=4096
LimitMEMLOCK=infinity

# Restart and reliability
Restart=always
RestartSec=10
StartLimitInterval=120
StartLimitBurst=3

# Timeout settings
TimeoutStartSec=45
TimeoutStopSec=30
TimeoutAbortSec=15

# Logging
StandardOutput=journal
StandardError=journal
SyslogIdentifier=foxhunt-backtesting

# Security settings
NoNewPrivileges=true
ProtectSystem=strict
ProtectHome=true
ProtectKernelTunables=true
ProtectKernelModules=true
ProtectControlGroups=true
RestrictRealtime=false
RestrictSUIDSGID=true

# Network restrictions (gRPC on localhost only)
RestrictAddressFamilies=AF_INET AF_INET6 AF_UNIX
IPAddressDeny=any
IPAddressAllow=localhost
IPAddressAllow=127.0.0.1
IPAddressAllow=::1

# Filesystem access
ReadWritePaths=/opt/foxhunt/data
ReadWritePaths=/opt/foxhunt/logs
ReadWritePaths=/opt/foxhunt/backtesting_results
ReadWritePaths=/tmp
ReadOnlyPaths=/opt/foxhunt/bin
ReadOnlyPaths=/opt/foxhunt/config

# Process management
KillMode=mixed
KillSignal=SIGTERM

[Install]
WantedBy=multi-user.target
Also=foxhunt.target

# MONITORING RECOMMENDATIONS:
# - Monitor CPU usage on cores 2-3
# - Track memory usage (can use up to 4GB for large backtests)
# - Monitor PostgreSQL connection health
# - Track backtesting job completion rates
# - Set up alerts for failed backtests
#
# PERFORMANCE NOTES:
# - Isolated CPU cores 2-3 to avoid trading interference
# - Higher memory limit for data-intensive backtesting
# - Normal scheduling priority (Nice=0)
# - Longer restart delay to handle heavy workloads
# - Extended timeout for large backtesting jobs