Tuning nginx

# This number should be, at maximum, the number of CPU cores on your system. 
worker_processes 16;
 
# Number of file descriptors used for Nginx. Should also be set in /etc/security/limits.conf
worker_rlimit_nofile 200000;
 
# only log critical errors
error_log /var/log/nginx/error.log crit
 
# Determines how many clients will be served by each worker process.
# (Max clients = worker_connections * worker_processes)
# "Max clients" is also limited by the number of socket connections available on the system (~64k)
worker_connections 4000;
 
# essential for linux, optmized to serve many clients with each thread
use epoll;
 
# Accept as many connections as possible, after nginx gets notification about a new connection.
# May flood worker_connections, if that option is set too low.
multi_accept on;
 
# Caches information about frequently accessed files. Try to experiment with those values.
open_file_cache max=200000 inactive=20s; 
open_file_cache_valid 30s; 
open_file_cache_min_uses 2;
open_file_cache_errors on;
 
# Disable access logs
access_log off;
 
# Sendfile copies data between one FD and other from within the kernel. 
# More efficient than read() + write(), since the requires transferring data to and from the user space.
sendfile on; 
 
# Tcp_nopush causes nginx to attempt to send its HTTP response head in one packet, 
# instead of using partial frames. This is useful for prepending headers before calling sendfile, 
# or for throughput optimization.
tcp_nopush on;
 
# don't buffer data-sends (disable Nagle algorithm). Good for sending frequent small bursts of data in real time.
tcp_nodelay on; 
 
# Timeout for keep-alive connections. Server will close connections after this time.
keepalive_timeout 30;
 
# Number of requests a client can make over the keep-alive connection. This is set high for testing.
keepalive_requests 100000;
 
# allow the server to close the connection after a client stops responding. Frees up socket-associated memory.
reset_timedout_connection on;
 
# send the client a "request timed out" if the body is not loaded by this time. Default 60.
client_body_timeout 10;
 
# If the client stops reading data, free up the stale client connection after this much time. Default 60.
send_timeout 2;
 
# Compression. Reduces the amount of data that needs to be transferred over the network
gzip on;
gzip_min_length 10240;
gzip_proxied expired no-cache no-store private auth;
gzip_types text/plain text/css text/xml text/javascript application/x-javascript application/xml;
gzip_disable "MSIE [1-6]\.";

# Increase system IP port limits to allow for more connections
net.ipv4.ip_local_port_range = 2000 65000
 
net.ipv4.tcp_window_scaling = 1
 
# number of packets to keep in backlog before the kernel starts dropping them 
net.ipv4.tcp_max_syn_backlog = 3240000
 
# increase socket listen backlog
net.core.somaxconn = 3240000
net.ipv4.tcp_max_tw_buckets = 1440000
 
# Increase TCP buffer sizes
net.core.rmem_default = 8388608
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.ipv4.tcp_rmem = 4096 87380 16777216
net.ipv4.tcp_wmem = 4096 65536 16777216
 
net.core.default_qdisc=fq
net.ipv4.tcp_congestion_control=bbr