The document discusses the internals and architecture of the Nginx web server. It covers Nginx's event-driven and non-blocking architecture, its use of memory pools and data structures like radix trees, how it processes HTTP requests through different phases, and how modules and extensions can be developed for Nginx. The document also provides an overview of Nginx's configuration, caching, and load balancing capabilities.

1. Nginx Internals [email_address]

2. Agenda What Why Architecture Infrastructure Http Module Conf & Location &Static Upstream & fastcgi Extension

3. What’s Nginx October 4, 2004 6.8% of the top 1 million HTTP Server Reverse proxy server Mail proxy server http://nginx.org/en/

4. Why Nginx Features : Nginx = transmit + apache Stability : Nginx > Lighttpd Performance : Nginx > Lighttpd > apache Security : Acess & Limit Zone & Limit Requests Community : sina/qq/tudou/taobao Third party modules more

5. Code Organization 117590 Core main/lib/data struct Event epool/time/mutex Http http server/upstream Os & mail

6. Architecture Multi-process Master+worker Event driven Non-blocking Single-threaded Highly modular Cache management process

7. Infrastructure String Array/List/Queue Hash Table Red black tree Memory pool Buff Radix Tree / Slab / Spinlock / shmtx http://code.google.com/p/nginxsrp/wiki/NginxCodeReview

8. Memory Management ngx_alloc ， ngx_calloc ， ngx_memalign Memory pool Avoid memory fragmentation and memory leaks Allocation once, deallocation once lifetime ： cycle 、 connection 、 Request Optimizing large memory allocation ngx_palloc ngx_pnalloc ngx_pcalloc ngx_pmemalign

9. Memory pool

10. Master process

11. Worker process

12. Master & woker Socketpair Accept Lock, avoid thundering herd Multi Accept Worker Processes Load-balance (7/8) Connection List per process Timeout handling. Red black tree

13. Config & command Command-style configuration files, if/echo Configuration block, ‘{}’ Support Include command Support inheritance(Http main/Server/Location) Multi-parameter Variables Conf demo

14. Config parse Type parse_file parse_block parse_param Command handler

15. Modular

16. Http Module http command, http {} ngx_http_block ngx_http_module_t

17. Http request processing 1 、 phase checker 2 、 phase handler, array 3 、 sub request

18. http phase NGX_HTTP_POST_READ_PHASE (realip) NGX_HTTP_SERVER_REWRITE_PHASE (Rewrite) NGX_HTTP_FIND_CONFIG_PHASE Can not be extended NGX_HTTP_REWRITE_PHASE (Rewite) NGX_HTTP_POST_REWRITE_PHAS E Can not be extended NGX_HTTP_PREACCESS_PHASE (limit_req 、 limit_zone 、 degradation 、 realip) NGX_HTTP_ACCESS_PHASE (ACCESS 、 auth_basic) NGX_HTTP_POST_ACCESS_PHASE Can not be extended NGX_HTTP_TRY_FILES_PHASE Can not be extended NGX_HTTP_CONTENT_PHASE (Autoindex 、 static 、 random_index 、 gzip_static) NGX_HTTP_LOG_PHASE

19. content phase handler vs content_handler checker: ngx_http_core_content_phase Fastcgi & autoindex

20. Nginx Filter Header Filter Content Filter ngx_http_send_header ngx_http_output_filter Example : gzip 、 more_set_header

21. Location features Exactly match Regular(sensitive/ insensitive) Location inheritance How to find the right location?

22. Location internals Ngx_http_block loc_conf ngx_http_init_locations Location inheritance check ngx_http_init_static_location_trees Ternary Search Tree(better than trie) Find location(ngx_http_core_find_location) first static location tree then regex locations

23. Static module Sendfile http://linux.die.net/man/2/sendfile NGX_HTTP_CONTENT_PHASE ngx_http_static_handler ngx_http_static_handler 1 、 method check. GET/HEAD/POST 2 、 Cache processing 3 、 ngx_http_discard_request_body 4 、 output Only Cache fd Red black tree

24. Nginx Upstream Protocol : Http/Fastcgi/Memcache/SCGI Load-balance: hash/random/round_robin Short connection Long connection only for memcached

25. Nginx Upstream ： fastcgi

26. Extension Develop Core Module Extension, such as nginx-php Http Module Extension Handler ： echo Filter ： gzip, usertrack upstream : fastcgi Load-balancers ： rand Emiller's Guide To Nginx Module Development

27. Extension Develop—where? Just before the server reads the config file For every configuration directive for the location and server for which it appears; When Nginx initializes the main configuration When Nginx initializes the server (i.e., host/port) configuration When Nginx merges the server configuration with the main configuration When Nginx initializes the location configuration When Nginx merges the location configuration with its parent server configuration When Nginx's master process starts When a new worker process starts When a worker process exits When the master exits Handling a request Filtering response headers Filtering the response body Picking a backend server Initiating a request to a backend server Re-initiating a request to a backend server Processing the response from a backend server Finishing an interaction with a backend server

28. Extension Develop—where?

29. Extension Develop—where?

30. Extension Develop—where? Http Phase handler Content_handler Header Filter Content Filter

31. Extension Develop—step “ Config” file ngx_addon_name=ngx_http_baidu_usertrack_module HTTP_AUX_FILTER_MODULES="$HTTP_AUX_FILTER_MODULES ngx_http_baidu_usertrack_module" NGX_ADDON_SRCS="$NGX_ADDON_SRCS $ngx_addon_dir/src/ngx_http_baidu_usertrack_module.c $ngx_addon_dir/src/baidu_des.c" NGX_ADDON_DEPS="$NGX_ADDON_DEPS $ngx_addon_dir/src/baidu_des.h" ORE_LIBS="$CORE_LIBS -lcrypto" Develop and build ./configure -add-module=path/to/your/new/module/directory Make Make install

32. Extension Develop—demo Demo

33. Q&A Q&A Thanks