TCP tuning: enable BBR

Enable Google BBR congestion control for better throughput

sysctl -w net.core.default_qdisc=fq net.ipv4.tcp_congestion_control=bbr

More linux commands

Show open UDP sockets

ss -ulnp

All UDP listening sockets with process info
Bind process to CPU cores

taskset -cp 0,1 <pid>

Pin a running process to specific CPU cores
Show hardware interrupts

watch -n1 'cat /proc/interrupts | head -30'

Per-CPU interrupt counts, updated every second
Show process limits

cat /proc/<pid>/limits

Hard and soft resource limits for a running process
Increase system file descriptor limit

ulimit -n 1048576 && echo '* soft nofile 1048576 * hard nofile 1048576' >> /etc/security/limits.conf

Set high FD limit for current session and persist it