13

We are not able to handle more than 3k concurrent request in nginx (Connecton time out). We change also the ulimit to 20000. Following are my nginx.conf and sysctl.conf files:

user www-data; 
worker_processes 4; 
pid /var/run/nginx.pid;
events {
     worker_connections 5000;
     use epoll;
     # multi_accept on; 
} # took it in next line
worker_rlimit_nofile    100000;

http {
     sendfile on;
     tcp_nopush on;
     tcp_nodelay on;
     keepalive_timeout 600;
     send_timeout 600;
     proxy_connect_timeout       600;
     proxy_send_timeout          600;
     proxy_read_timeout          600;
     reset_timedout_connection on;
     types_hash_max_size 2048;
     client_header_buffer_size 5k;
     open_file_cache max=10000 inactive=30s;
     open_file_cache_valid    60s;
     open_file_cache_min_uses 2;
     open_file_cache_errors   on;
     include /etc/nginx/mime.types;
     default_type application/octet-stream;
     access_log off; 
     error_log /var/log/nginx/error.log;
     gzip on;
     gzip_disable "msie6";
     include /etc/nginx/conf.d/*.conf;
     include /etc/nginx/sites-enabled/*; 
}

systel.conf

# Increase size of file handles and inode cache
fs.file-max = 2097152

# Do less swapping
vm.swappiness = 10
vm.dirty_ratio = 60
vm.dirty_background_ratio = 2

### GENERAL NETWORK SECURITY OPTIONS ###

# Number of times SYNACKs for passive TCP connection.
net.ipv4.tcp_synack_retries = 2

# Allowed local port range
net.ipv4.ip_local_port_range = 2000 65535

# Protect Against TCP Time-Wait
net.ipv4.tcp_rfc1337 = 1

# Decrease the time default value for tcp_fin_timeout connection
net.ipv4.tcp_fin_timeout = 15

# Decrease the time default value for connections to keep alive
net.ipv4.tcp_keepalive_time = 300
net.ipv4.tcp_keepalive_probes = 5
net.ipv4.tcp_keepalive_intvl = 15

### TUNING NETWORK PERFORMANCE ###

# Default Socket Receive Buffer
net.core.rmem_default = 31457280

# Maximum Socket Receive Buffer
net.core.rmem_max = 12582912

# Default Socket Send Buffer
net.core.wmem_default = 31457280

# Maximum Socket Send Buffer
net.core.wmem_max = 12582912

# Increase number of incoming connections
net.core.somaxconn = 65536

# Increase number of incoming connections backlog
net.core.netdev_max_backlog = 65536

# Increase the maximum amount of option memory buffers
net.core.optmem_max = 25165824

# Increase the maximum total buffer-space allocatable
# This is measured in units of pages (4096 bytes)
net.ipv4.tcp_mem = 65536 131072 262144
net.ipv4.udp_mem = 65536 131072 262144

# Increase the read-buffer space allocatable
net.ipv4.tcp_rmem = 8192 87380 16777216
net.ipv4.udp_rmem_min = 16384

# Increase the write-buffer-space allocatable
net.ipv4.tcp_wmem = 8192 65536 16777216
net.ipv4.udp_wmem_min = 16384

# Increase the tcp-time-wait buckets pool size to prevent simple DOS attacks
net.ipv4.tcp_max_tw_buckets = 1440000
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_tw_reuse = 1

We are using ubuntu OS with 4 CPU and 8 GB RAM. I hardly see any CPU and RAM usage. I am just firing nginx default page URL.

Community
  • 1
user50442
  • 241

2 Answers2

7

I strongly suggest you to use micro-caching.

Example : http://www.howtoforge.com/why-you-should-always-use-nginx-with-microcaching http://reviewsignal.com/blog/2014/06/25/40-million-hits-a-day-on-wordpress-using-a-10-vps/

I recently set up micro-caching on my box. With apache benchmark it holds up to 50 000 connections , CPU goes only to 6%. No timeouts, page is served in 1,1ms.

Those example manuals above i suggest only for "view only", because they are not correct. In my case , I spent many hours setting this up, but it is worth that stress :)

Jānis Konošonoks
  • 211
2

You mention you set user file limit to 20000 but not how..

On Ubuntu you change the hard and soft limits in /etc/security/limits.conf Assuming the user who is running nginx is www-data, you would then just add this at end of file:

www-data soft nofile 100000
www-data hard nofile 120000
www-data soft nproc 100000
www-data hard nproc 120000

If you want to check what your current limit is run:

su - www-data
ulimit -Hn
ulimit -Sn
Flup
  • 8,398
Alex R
  • 2,535