epoll_wait() reported that client prematurely closed connection

[ole-lukoje]

Проблема в том, что на проксируемом сервере происходят ошибки типа "An
exception occured writing the response entity. Broken pipe", их нужно
устранить.
По всей видимости они возникают из-за того, что nginx рвет соединение с
проксируемым сервером, не уверены что это не будет приводить к утечкам
памяти в следствии
такого типа завершения соединения.

CentOS release 6.5
Linux version 2.6.32-431.el6.x86_64
nginx/1.5.8

Содержимое файла конфигурации:

user nginx;

worker_processes  8;
timer_resolution 100ms;
worker_rlimit_nofile 50000;
worker_priority -5;

error_log        	/var/log/nginx/error.log  info;
pid               	/var/run/nginx.pid;

events {
    worker_connections  25000;
    use epoll;
}

http {

    include       mime.types;
    default_type  application/x-javascript;

    log_format main '$remote_addr - $remote_user [$time_local] $request '
					'"$status" $body_bytes_sent "$http_referer" '
					'"$http_user_agent" "$http_x_forwarded_for"';

    chunked_transfer_encoding off;

    gzip on;
    gzip_static on;
    gzip_min_length 640;
    gzip_buffers 64 8k;
    gzip_comp_level 4;
    gzip_http_version 1.1;
    gzip_proxied any;
    gzip_types text/plain application/xml application/x-javascript
text/css;
    gzip_disable "MSIE [1-6]\.(?!.*SV1)";
    gzip_vary on;

    output_buffers   32 512k;
    sendfile_max_chunk  128k;			
    postpone_output  1460;				
    server_names_hash_bucket_size 64;	

    tcp_nopush on;			
    tcp_nodelay on;			

    client_max_body_size       1m;			
    client_body_buffer_size    128k;		
    client_header_buffer_size    1k;		
    large_client_header_buffers  4 4k;		

    keepalive_timeout      45 45;		
    client_header_timeout  45;			
    client_body_timeout    45;			
    send_timeout           45;			
    reset_timedout_connection on;		

    memcached_connect_timeout 60s;		
    memcached_read_timeout 60s;			
    memcached_send_timeout 60s;			

    charset                 utf-8;		
    source_charset          utf-8;		
    ignore_invalid_headers     on;		
    keepalive_requests        100;		
    recursive_error_pages     off;		
    server_tokens             off;		
    server_name_in_redirect   off;		
    sendfile                   on;		

    open_file_cache           max=1000 inactive=20s;	
    open_file_cache_valid     30s;		
    open_file_cache_min_uses  2;		
    open_file_cache_errors    on;		

	#######################################################################
    # PUSH_STREAM_MODULE GLOBAL SETTINGS (COMET)
    #######################################################################

    #The size of the memory chunk this module will use to store published
messages,
    #channels and other shared structures. When this memory is full any new
request
    #for publish a message or subscribe a channel will receive an 500
Internal Server Error response.
    push_stream_shared_memory_size 100M;

    #Maximum permissible channel id length (number of characters).
    #Longer ids will receive an 400 Bad Request response. I
    push_stream_max_channel_id_length           50;

    #The length of time a subscriber will stay connected before it is
considered expired and disconnected.
    #If you do not want subscribers to be automatically disconnected, just
not set this directive.
    #But, this operation is very important to help Nginx recycle memory
consumed to send messages to susbscriber,
    #allocated at pool request.
    push_stream_subscriber_connection_ttl      5m;
    push_stream_longpolling_connection_ttl     5m;

    push_stream_wildcard_channel_prefix  "broadcast_";
    proxy_cache_path  /var/cache/nginx/ftl levels=1:2
keys_zone=ftl-cache:20m max_size=100m inactive=120m; 

	upstream  memcached_cluster  {
		server   127.0.0.1:11211;
		hash   $uri/3.8;
		hash_again  1000;          
		keepalive 512;		
	}

   server {
        listen                   *:80;
        server_name_in_redirect   off;
        server_name test.example.com;   

        proxy_connect_timeout      60s;		
        proxy_send_timeout         60s;		
        proxy_read_timeout         60s;		

        proxy_buffering          on;		
        proxy_buffer_size        64k;		
        proxy_buffers            4 64k;		
        proxy_busy_buffers_size 128k;		
        proxy_temp_file_write_size 10m;		
        proxy_headers_hash_bucket_size 256;	

        proxy_set_header  Host        $host:$server_port;				
        proxy_set_header  X-Real-IP  $remote_addr;						
        proxy_set_header  X-Forwarded-For $proxy_add_x_forwarded_for;	
        access_log  /var/log/nginx/nginx.log  main;						
        log_not_found off;  		
        root /var/spool/nginx/;		

		location /portal-facade-ng/v1/btv/imageMap/ {
			if ($request_method != GET) {
				proxy_pass http://127.0.0.1:8080;
				break;
			}

			add_header  Cache-Control  no-cache;
			add_header  Content-Type   image/png;
			default_type  image/png;
			set     $memcached_key   "$uri/3.8";
			memcached_pass  memcached_cluster;
		}


		location /portal-facade-ng/v1/btv/epg/current/ {
			if ($request_method != GET) {
				proxy_pass http://127.0.0.1:8080;
				break;
			}
			set     $memcached_key   "$uri/3.8";
			memcached_pass  memcached_cluster;
		}

		location /portal-facade-ng/v1/btv/epgGrid/bar/image/ {
			if ($request_method != GET) {
				proxy_pass http://127.0.0.1:8080;
				break;
			}

			add_header  Cache-Control  no-cache;
			add_header  Content-Type   image/png;
			default_type  image/png;
			set     $memcached_key   "$uri/3.8";
			memcached_pass  memcached_cluster;
		}
	}
}

Posted at Nginx Forum: http://forum.nginx.org/read.php?21,253351,253363#msg-253363