Socket ack鏄寚褰?/span>socket鎺ユ敹鍒版暟鎹箣鍚庯紝鍙戦佷竴涓?/span>ack瀛楃涓?/span>(姣斿$ACK)緇?/span>socket鍙戦佹柟銆傝繖鏍鳳紝socket鍙戦佹柟鍙互鏍規(guī)嵁鏄惁鏀跺埌浜?/span>ack鍒ゆ柇瀵規(guī)柟鏄惁鏀跺埌浜?jiǎn)鏁版嵁銆?/span>
Socket ack鏄樉紺虹殑鍦ㄥ簲鐢ㄧ▼搴忎腑鍔犲叆鐨勪竴縐嶉氳鍗忚銆傚鏋滀笉浣跨敤ack錛屽湪socket閫氳涓紝鍙兘浼?xì)涓㈠け鏁版嵁銆?/span>
姣斿錛?/span>socket client瑕佽繛緇殑緇?/span>socket server鍙戦?/span>100鏉℃秷鎭傚鏋滄垜浠湪server鏀跺埌絎?/span>50鏉℃秷鎭殑鏃跺欙紝寮鴻kill浜?/span>server銆傞偅涔堟煡璇?/span>client绔彂閫佺殑log錛屽彲鑳?/span>client绔垚鍔熷彂閫佷簡(jiǎn)51鏉°傚彧鏈夊綋client绔彂閫佺52鏉℃秷鎭殑鏃跺欐墠閬囧埌寮傚父銆傝繖鏍風(fēng)51鏉℃秷鎭氨涓㈠け浜?jiǎn)銆?/span>
鎵浠ヤ負(fù)浜?jiǎn)纭繚鏁版嵁浼犺緭鐨勫噯纭э紝鎴戜滑鍙互寮曞叆ack鍗忚銆傛湁鏃舵垜浠笉浠呰紜繚server涓嶄絾鏀跺埌浜?jiǎn)鏁版嵁锛岃屼笖榪樿淇濊瘉server鎴愬姛澶勭悊浜?jiǎn)鏁版嵁銆傝繖鏃訛紝鍙互絳?/span>server鎴愬姛澶勭悊瀹屾暟鎹箣鍚庯紝鍐嶇粰client鍙?/span>ack銆?/span>
2. Socket Keep Alive
Socket榪炴帴鍍忔暟鎹簱榪炴帴涓鏍鳳紝灞炰簬閲嶉噺鍨嬭祫婧愩傚鏋滄垜浠綣佺殑鍒涘緩socket銆佸彂閫?/span>/鎺ユ敹鏁版嵁銆佸叧闂?/span>socket錛岄偅涔堜細(xì)鏈夊緢澶т竴閮ㄥ垎鏃墮棿嫻垂鍦?/span>socket鐨勫垱寤哄拰鍏抽棴涓娿?/span>
鎵浠ワ紝濡傛灉鎴戜滑緇忓父闇瑕佷笌鍚屼竴涓?/span>socket鍦板潃鍙戦?/span>/鎺ユ敹鏁版嵁鏃訛紝搴旇鑰冭檻鍙垱寤轟竴嬈?/span>socket錛岀劧鍚庝竴鐩翠嬌鐢ㄨ繖涓?/span>socket瀵硅薄鍙戦?/span>/鎺ユ敹鏁版嵁銆?/span>
3. Heartbeat
閫氬父錛屾垜浠細(xì)璁劇疆socket鐨?/span>receive timeout銆傝繖鏍鳳紝濡傛灉鎴戜滑涓鐩存墦寮鐫socket (keep alive)錛?/span> 鑰屽緢闀挎椂闂村張娌℃湁鏁版嵁閫氳錛?/span>socket鎺ユ敹鏂瑰氨浼?/span>timeout錛屾渶緇堝鑷存墦寮鐨勮繛鎺ュ潖鎺夈?/span>
濡傛灉寰堥暱鏃墮棿娌℃湁鏁版嵁閫氳錛岄槻鐏鎴栦唬鐞嗘湇鍔″櫒涔熷彲鑳戒細(xì)鍏抽棴鎵撳紑鐨?/span>socket榪炴帴銆?/span>
鎵浠ヤ負(fù)浜?jiǎn)淇濊瘉鎵撳紑鐨?/span>socket榪炴帴涓鐩村彲鐢紝濡傛灉涓孌墊椂闂存病鏈夋暟鎹繘琛岄氳錛堟垨鎸囧畾涓涓椂闂撮棿闅旓級(jí)錛屾垜浠彲浠ユ樉紺虹殑鍙戦佷竴涓?/span>heartbeat娑堟伅(姣斿: $HRT)緇欏鏂癸紝浠庤屼繚璇佽繛鎺ヤ笉浼?xì)琚紓甯稿叧闂?/span>
4. Socket Close
姣忎竴涓猻ocket瀵硅薄浼?xì)鎸佹湁涓涓猻ocket descriptor (鍏跺疄灝辨槸file descriptor)錛屾搷浣滅郴緇熷浜巗ocket descriptor鏈変竴涓渶澶ч檺鍒?/span>銆傚洜姝ゅ綋socket涓嶅啀浣跨敤鏃訛紝涓瀹氳璁板緱鍏抽棴錛屽嵆浣?/span>socket榪炴帴澶辮觸鎴栧嚭鐜板紓甯革紝鍙socket瀵硅薄涓嶄負(fù)null錛屼竴瀹氳璁板緱鍏抽棴銆?/span>
涓嬮潰鍥炬樉紺轟簡(jiǎn)錛屽綋socket鍏抽棴鏃訛紝socket鐨勭姸鎬佸彉鍖?/span>(socket鐘舵佸彲浠ラ氳繃netstat鍛戒護(hù)鏌ョ湅)銆傛洿璇︾粏鐨勮В閲婏紝鍙互google涓涓嬨?br />
褰撲富鍔ㄤ竴鏂硅皟鐢?/span>close(鍏堣皟鐢?/span>close)鏃剁殑鐘舵佸彉鍖?/span>:
ESTABLISHED -> FIN_WAIT_1-> FIN_WAIT_2 -> TIME_WAIT -> CLOSED
褰撹鍔ㄤ竴鏂硅皟鐢?/span>close(鍚庤皟鐢?/span>close)鏃剁殑鐘舵佸彉鍖?/span>:
ESTABLISHED -> CLOSE_WAIT -> LAST_ACK -> CLOSED
閫氬父錛?/span>TIME_WAIT 鏄甯哥姸鎬侊紝榪囦竴孌墊椂闂?/span>(2MSL, 1鍒?/span>4鍒嗛挓)灝變細(xì)鑷姩娑堝け.
鎴戜滑闇瑕佺壒鍒敞鎰?/span>CLOSE_WAIT 鐘舵侊細(xì)
1錛?span style="font: 7pt 'Times New Roman'"> 濡傛灉寰堥暱鏃墮棿鎵嶆秷澶憋紝琛ㄦ槑socket server澶勭悊澶參錛屽緢澶?/span>client宸茬粡榪炴帴鍒?/span>server錛屽彂閫佸畬鏁版嵁騫?/span>close浜?jiǎn)銆?/span>
2錛?span style="font: 7pt 'Times New Roman'"> 濡傛灉涓鐩翠篃涓嶆秷澶憋紝琛ㄦ槑鏈?/span>socket娌℃湁姝ｅ父close (瀵規(guī)柟宸茬粡close浜?/span>)
5. SO_REUSEADDR Option
褰?/span>socket涓誨姩璋冪敤close鐨勬椂鍊欙紝浠庝笂闈㈠彲浠ョ煡閬擄紝瀹冩渶緇堜細(xì)榪涘叆TIME_WAIT 鐘舵侊紝闇瑕佽繃1鍒?/span>4鍒嗛挓錛屾墠鑳藉畬鍏?/span>close銆?/span>
褰?/span>socket澶勪簬TIME_WAIT 鐘舵佹椂錛屽畠浠嶇劧鍗犵敤姝ｅ湪浣跨敤鐨?/span>IP/PORT銆傝繖鏍鳳紝濡傛灉鎴戜滑鐨勭▼搴?/span>(姣斿socket server)浣跨敤浜?jiǎn)涓涓浐瀹氱殑IP/PORT錛屽綋socket澶勪簬TIME_WAIT 鐘舵佹椂錛岀▼搴忓皢涓嶈兘绔嬪嵆閲嶅惎錛屼細(xì)鍑虹幇绔彛鍗犵敤閿欒銆?/span>
Socket鎻愪緵浜?jiǎn)涓涓?/span>setReuseAddress()鏂規(guī)硶錛屽彲浠ヨ緗綋socket澶勪簬TIME_WAIT 鐘舵佹椂錛屾槸鍚﹀厑璁稿叾瀹冭繘紼嬬粦瀹氳繖涓鍙ｃ?/span>
濡傛灉鎴戜滑姝ｅ湪寮鍙?/span>socket server錛屼竴瀹氳璁板緱璋冪敤ServerSocket.setReuseAddress(true).
Client socket涔熸湁榪欎釜鏂規(guī)硶錛岃屼笖鏈夋椂鍙兘闇瑕佹寚鏄?/span>client榪炴帴server鏃舵墍浣跨敤鐨勬湰鍦?/span>IP/PORT(涓鑸笉鐢ㄦ寚鏄庯紝緋葷粺浼?xì)闅忔満閫夋嫨涓涓?/span>PORT)銆備絾瀹為檯嫻嬭瘯錛屽湪client socket涓婅緗繖涓柟娉曞湪Windows鍜?/span>Solaris涓嬪茍涓嶈搗浣滅敤銆傚綋socket澶勪簬TIME_WAIT 鐘舵佹椂錛岄噸鍚?/span>client浠嶇劧鍑虹幇绔彛鍗犵敤閿欒銆備笂緗戞悳绱簡(jiǎn)寰堥暱鏃墮棿錛屽緢澶氫漢閮界鍒頒簡(jiǎn)榪欎釜闂錛屽彲鑳芥槸鎿嶄綔緋葷粺搴曞眰socket瀹炵幇闂銆傚洜涓烘祴璇曚嬌鐢?/span>C璇█寮鍙戠殑socket client錛屽悓鏍蜂篃鏈夎繖涓敊璇傛湁浜鴻LINUX涓嬪ソ鐢紝榪樻湁灝辨槸鍙互灝濊瘯淇敼tcp_time_wait_interval鏉ュ噺灝?/span>TIME_WAIT絳夊緟鏃墮棿
鏈榪戜竴鐩村湪鍋歋ocket紼嬪簭錛岃繖閲屾妸涓浜汼ocket紼嬪簭鐨勬敞鎰忎簨欏規(guī)葷粨涓涓嬨備粖澶╁厛璇磋Socket涓殑Timeout錛屽叾瀹冪殑涓嬫琛ュ叏銆?br />
1. Socket Timeout
鍐?/span>Socket紼嬪簭鐨勬椂鍊欓渶瑕佹敞鎰忚緗笅闈㈢殑timeout錛岄伩鍏嶅鏂規(guī)病鏈夊搷搴旂殑鏃跺欙紝瀵艱嚧Socket紼嬪簭鎸傝搗鎴栫瓑寰呮椂闂磋繃闀?/span>
1.1 Accept Timeout
Accept timeout 浠呭ServerSocket鏈夌敤銆?/span>ServerSocket 浣跨敤accept()鏂規(guī)硶鏉ョ洃鍚鎴風(fēng)Socket鐨勮繛鎺ャ?/span>
榛樿錛?/span>ServerSocket.accept() 鏂規(guī)硶浼?xì)涓鐩撮樆濉炵洿鍒版湁瀹㈡埛绔潵榪炴帴銆傞氬父錛屾垜浠笉闇瑕佽緗?/span>accept timeout.
浣嗘湁鏃跺欑壒孌婃儏鍐碉紝榪樻槸瑕佽冭檻璁劇疆accept timeout.
姣斿: 紼嬪簭A緇欑▼搴?/span>B鍙戜簡(jiǎn)涓涓?/span>JMS娑堟伅錛岀劧鍚庣▼搴?/span>A鍚姩涓涓?/span>Socket Server錛屾兂閫氳繃socket絳夊緟鎺ユ敹紼嬪簭B鐨勮繑鍥炴秷鎭傚鏋滀笉璁劇疆accept timeout, 騫朵笖紼嬪簭B鍥犱負(fù)鏌愪簺鍘熷洜涓鐩翠笉鑳借繛鎺?/span>Socket Server錛屾渶緇堜細(xì)瀵艱嚧紼嬪簭A鎸傝搗銆?/span>
Accept Timeout鍙互榪欐牱璁劇疆錛?/span>
ServerSocket serverSocket = new ServerSocket(5555);
serverSocket.setSoTimeout(5000); // in milliseconds
while (true) {
Socket socket = serverSocket.accept();
…
}
1.2 Connect Timeout
褰?/span>Client绔繛鎺?/span>Server绔殑鏃跺欙紝鍙互鎸囧畾Connect Timeout
濡傛灉娌℃湁鎸囧畾錛屼細(xì)浣跨敤鎿嶄綔緋葷粺鐨勯粯璁ゅ?/span>:
|
OS |
Default TCP timeout |
|
BSD |
75 seconds |
|
Linux |
189 seconds |
|
Solaris |
225 seconds |
|
Windows XP |
21 seconds |
Connect Timeout鍙互榪欐牱璁劇疆錛?/span>
SocketAddress socketAddress = new InetSocketAddress(host, port);
socket = new Socket();
socket.connect(socketAddress, connectTimeout);
1.3 Receive Timeout
褰?/span>socket浠庡彟涓鏂規(guī)帴鏀舵暟鎹椂錛屽彲浠ヨ緗?/span>Receive Timeout
榛樿娌℃湁timeout錛?/span>socket浼?xì)涓鐩撮樆濉炵洿鍒版湁鏁版嵁鍙鍙栥?/span>
Receive Timeout鍙互榪欐牱璁劇疆錛?/span>
Socket socket = new Socket(host, port);
socket.setSoTimeout(timeout);
1.4 Send Timeout
Send Timeout鏄?/span>socket緇欏彟涓鏂瑰彂閫佹暟鎹椂浣跨敤鐨勩?/span>
涓嶈繃Java閲屾病鏈夊姙娉曡緗?/span>Send Timeout.
褰撶劧錛?/span>socket鍙戦佹暟鎹殑鏃跺欙紝浼?xì)棣栧厛鍙戦佸埌鏈満OS鐨勪竴涓?/span>buffer鍐呫備竴鑸彧瑕佷竴嬈″彂閫佺殑鏁版嵁涓嶆槸寰堝ぇ錛屽嵆浣垮鏂規(guī)寕璧鋒垨鏆傛椂涓嶈兘鎺ユ敹鏁版嵁錛屼篃涓嶄細(xì)瀵艱嚧鍙戦佹柟鎸傝搗銆?/span>