http://news.netcraft.com/
這個是一個統計當前web服務器的各種信息的網站!
由上圖可知，nginx穩坐第三名，羣衆的眼睛都是雪亮的！nginx會超過微軟的IIS！
http://nginx.org/ 官方網站
nginx採用epoll事件模型（內核2.6以上支持！），I/O效率相當高！（Apache採用select機制，穩定）
具體爲什麼可以參看
http://www.cppblog.com/converse/archive/2008/10/12/63836.html
http://xinlogs.com/nginx-epool-events
nginx [engine x] is anHTTP and reverse proxy server,as well as a mail proxy server, written byIgor Sysoev. For a long time, it has been runningon many heavily loaded Russian sites includingYandex,Mail.Ru,VKontakte, andRambler. According to Netcraft nginx served orproxied10.09% busiest sites in April 2012. Here are someof the success stories:FastMail.FM,Wordpress.com.
讀法，enginex 貌似我一直都讀錯的，擦淚！HTTP服務器，反向代理（proxy）服務器,郵件反向代理，是個俄羅斯人寫的，單臺nginx服務器可以處理時5萬個併發，Apache最多隻能處理3000個，但是Apache穩定且功能衆多，所以nginx做了衆多網站的反向代理服務器，作爲負載均衡，咱們精弘網絡也是Apache做後臺，tomcat處理jsp，而nginx處理靜態頁面！
The sources are distributed under the2-clause BSD-likelicense.
Basic HTTP server features
Serving static and index files, andautoindexing;open
file descriptor cache;
處理靜態主頁，自動索引，作爲文件描述符的緩存，這樣再次訪問特別快！
Accelerated reverse proxying with caching;simple load balancing
and fault tolerance;
用cache加速反向代理！（這裏可以對比一下squid服務！squid與apache相同屬於重量級的反向代理，一次相對有varnish這款緩存在內存中的！）
Accelerated support with caching ofFastCGI, uwsgi, SCGI, andmemcached servers;simple load balancing and fault tolerance;
memcached是分佈式的內存緩存服務器！fastcgi（php）uwsgi（python）nginx本身的緩存機制不如varnish等，varnish與squid的緩存能力很強！而nginx對於HTTP請求的處理能力很強！通常的架構一般是這樣的：前端nginx只做反向代理處理HTTP請求，不做任何緩存。後端直接指向varnish或squid做爲緩存，在後面是Apache實現web應用！所以沒有一種超級NB的服務軟件的把所有事都給幹了，所以想要有市場份額，你就必須有超出其他服務的特長！做人亦如此！
Modular architecture. （模塊化）Filters includegzipping, byte ranges, chunked responses,XSLT,SSI,
andimage transformation filter. Multiple SSIinclusions within a single page can be processed in parallel if they arehandled by proxied or FastCGI
servers;
SSL and TLS SNI support.
淘寶使用nginx，但是對於淘寶這麼誇張的pv數，nginx某些時候不夠用，淘寶就針對這個再做了 一個tengine的web服務器！
官網如下，http://tengine.taobao.org/index_cn.html （tengine是開源產品哦！來自淘寶核心系統開發部門，讓偶想起了上次的OceanBase！）
Other HTTP server features
Name-based and IP-basedvirtual servers;
基於域名或者IP的虛擬主機
Keep-alive and pipelined connectionssupport;
Flexible configuration;
Reconfiguration andupgradeof an executable without interruption of
the client servicing;
重寫配置，可以不打斷當前用戶請求
Access log formats,buffered log writing, andfastlog rotation;
日誌格式，可以緩存日誌！（日誌會涉及磁盤讀寫，可以先緩存，在一次寫入，提高磁盤效率），支持快速日誌滾動！
3xx-5xx error codesredirection;
自定義錯誤頁面，我們的404,500等錯誤頁面
The rewrite module:URI changing using regular expressions;
重寫模塊，URI（同一資源定位符）
根據url，域名的不同，將http請求發到不同的服務器分組
Executing different functions depending ontheclient address;
基於客戶端地址的不同執行不同的功能模塊
Access control based onclient IP address andHTTP
Basic authentication;
Validation ofHTTP referer;
ThePUT, DELETE, MKCOL, COPY, and MOVE methods;
FLV andMP4 streaming;
各種流媒體視頻格式
響應速度限制，例如：凡是來自於上海的IP響應爲5K/s,杭州的500K/s
Limiting the number of simultaneousconnections orrequests coming from one address;
可以啓用Perl（啊!）
Mail proxy server features
User redirection to IMAP/POP3 backend using an external HTTP authenticationserver;
User authentication using an external HTTP authentication server and connectionredirection to an internal SMTP backend;
- Authentication methods:
- POP3: USER/PASS, APOP, AUTH LOGIN/PLAIN/CRAM-MD5;
- IMAP: LOGIN, AUTH LOGIN/PLAIN/CRAM-MD5;
- SMTP: AUTH LOGIN/PLAIN/CRAM-MD5;
- SSL support;
- STARTTLS and STLS support.
Architecture and scalability
- One master and several worker processes; worker processes run under an unprivileged user;
- The notification methods: kqueue (FreeBSD 4.1+), epoll (Linux 2.6+), rt signals (Linux 2.2.19+), /dev/poll (Solaris 7 11/99+), event ports (Solaris 10), select, and poll;
- 各種機制，你說咋就沒Windows呢？！
- The support of the various kqueue features including EV_CLEAR, EV_DISABLE (to temporarily disable events), NOTE_LOWAT, EV_EOF, number of available data, error codes;
- sendfile (FreeBSD 3.1+, Linux 2.2+, Mac OS X 10.5+), sendfile64 (Linux 2.4.21+), and sendfilev (Solaris 8 7/01+) support;
- 啥叫sendfile？用戶空間與內核空間的切換！
(FreeBSD 4.3+, Linux 2.6.22+);
(FreeBSD 4.4+, Linux 2.4+, Solaris 2.6+, Mac OS X);
- Accept-filters (FreeBSD 4.1+) and TCP_DEFER_ACCEPT (Linux 2.4+)support;
- 10,000 inactive HTTP keep-alive connections take about 2.5M memory;
- 10000的HTTP在線請求僅佔用2.5M內存！
- Data copy operations are kept to a minimum.
Tested OS and platforms
- FreeBSD 3 — 10 / i386; FreeBSD 5 — 10 / amd64;
- Linux 2.2 — 3 / i386; Linux 2.6 — 3 / amd64;
- Solaris 9 / i386, sun4u; Solaris 10 / i386, amd64, sun4v;
- AIX 7.1 / powerpc
- Mac OS X / ppc, i386;
- Windows XP, Windows Server 2003.
雖然上面講了這麼多，但nginx並非牛上了天，要不然Apache也不是老大哥！
源碼安裝咱直接省略了（最新的1.2穩定版在4.23放出！）
關於memcached，這塊需要好好學習！
memcached注意與memcache的區別，一個d哦！咱php的memcache是php的API！（重要哦）
各個語言都有各自的memcached客戶端！
nginx也有memcached的客戶端
大型web解決方案可以還有
CDN加速！（contentdelivery network）
智能DNS（DNSPOD，dns.la）
關於nginx的配置文件，請參考我其他的nginx系列學習筆記。