鍦ㄩ樆濉炴ā寮忎笅, send鍑芥暟鐨勮繃紼嬫槸灝嗗簲鐢ㄧ▼搴忚姹傚彂閫佺殑鏁版嵁鎷瘋礉鍒板彂閫佺紦瀛樹腑鍙戦佸茍寰楀埌紜鍚庡啀榪斿洖.浣嗙敱浜庡彂閫佺紦瀛樼殑瀛樺湪,琛ㄧ幇涓?濡傛灉鍙戦佺紦瀛樺ぇ灝忔瘮璇鋒眰鍙戦佺殑澶у皬瑕佸ぇ,閭ｄ箞send鍑芥暟绔嬪嵆榪斿洖,鍚屾椂鍚戠綉緇滀腑鍙戦佹暟鎹?鍚﹀垯,send鍚戠綉緇滃彂閫佺紦瀛樹腑涓嶈兘瀹圭撼鐨勯偅閮ㄥ垎鏁版嵁,騫剁瓑寰呭绔‘璁ゅ悗鍐嶈繑鍥?鎺ユ敹绔彧瑕佸皢鏁版嵁鏀跺埌鎺ユ敹緙撳瓨涓?灝變細紜,騫朵笉涓瀹氳絳夊緟搴旂敤紼嬪簭璋冪敤recv);
鍦ㄩ潪闃誨妯″紡涓?send鍑芥暟鐨勮繃紼嬩粎浠呮槸灝嗘暟鎹嫹璐濆埌鍗忚鏍堢殑緙撳瓨鍖鴻屽凡,濡傛灉緙撳瓨鍖哄彲鐢ㄧ┖闂翠笉澶?鍒欏敖鑳藉姏鐨勬嫹璐?榪斿洖鎴愬姛鎷瘋礉鐨勫ぇ灝?濡傜紦瀛樺尯鍙敤絀洪棿涓?,鍒欒繑鍥?1,鍚屾椂璁劇疆errno涓篍AGAIN.
linux涓嬪彲鐢╯ysctl -a | grep net.ipv4.tcp_wmem鏌ョ湅緋葷粺榛樿鐨勫彂閫佺紦瀛樺ぇ灝? net.ipv4.tcp_wmem = 4096 16384 81920 榪欐湁涓変釜鍊?絎竴涓兼槸socket鐨勫彂閫佺紦瀛樺尯鍒嗛厤鐨勬渶灝戝瓧鑺傛暟,絎簩涓兼槸榛樿鍊?璇ュ間細琚玭et.core.wmem_default瑕嗙洊),緙撳瓨鍖哄湪緋葷粺璐熻澆涓嶉噸鐨勬儏鍐典笅鍙互澧為暱鍒拌繖涓?絎笁涓兼槸鍙戦佺紦瀛樺尯絀洪棿鐨勬渶澶у瓧鑺傛暟(璇ュ間細琚玭et.core.wmem_max瑕嗙洊). 鏍規嵁瀹為檯嫻嬭瘯,濡傛灉鎵嬪伐鏇存敼浜唍et.ipv4.tcp_wmem鐨勫?鍒欎細鎸夋洿鏀圭殑鍊兼潵榪愯,鍚﹀垯鍦ㄩ粯璁ゆ儏鍐典笅,鍗忚鏍堥氬父鏄寜net.core.wmem_default鍜宯et.core.wmem_max鐨勫兼潵鍒嗛厤鍐呭瓨鐨?
搴旂敤紼嬪簭搴旇鏍規嵁搴旂敤鐨勭壒鎬у湪紼嬪簭涓洿鏀瑰彂閫佺紦瀛樺ぇ灝? socklen_t sendbuflen = 0; socklen_t len = sizeof(sendbuflen); getsockopt(clientSocket, SOL_SOCKET, SO_SNDBUF, (void*)&sendbuflen, &len); printf("default,sendbuf:%d\n", sendbuflen); sendbuflen = 10240; setsockopt(clientSocket, SOL_SOCKET, SO_SNDBUF, (void*)&sendbuflen, len); getsockopt(clientSocket, SOL_SOCKET, SO_SNDBUF, (void*)&sendbuflen, &len); printf("now,sendbuf:%d\n", sendbuflen); 闇瑕佹敞鎰忕殑鏄?铏界劧灝嗗彂閫佺紦瀛樿緗垚浜?0k,浣嗗疄闄呬笂,鍗忚鏍堜細灝嗗叾鎵╁ぇ1鍊?璁句負20k.
-------------------瀹炰緥鍒嗘瀽---------------
鍦ㄥ疄闄呭簲鐢ㄤ腑,濡傛灉鍙戦佺鏄潪闃誨鍙戦?鐢變簬緗戠粶鐨勯樆濉炴垨鑰呮帴鏀剁澶勭悊榪囨參,閫氬父鍑虹幇鐨勬儏鍐墊槸,鍙戦佸簲鐢ㄧ▼搴忕湅璧鋒潵鍙戦佷簡10k鐨勬暟鎹?浣嗘槸鍙彂閫佷簡2k鍒板绔紦瀛樹腑,榪樻湁8k鍦ㄦ湰鏈虹紦瀛樹腑(鏈彂閫佹垨鑰呮湭寰楀埌鎺ユ敹绔殑紜).閭ｄ箞姝ゆ椂,鎺ユ敹搴旂敤紼嬪簭鑳藉鏀跺埌鐨勬暟鎹負2k.鍋囧鎺ユ敹搴旂敤紼嬪簭璋冪敤recv鍑芥暟鑾峰彇浜?k鐨勬暟鎹湪澶勭悊,鍦ㄨ繖涓灛闂?鍙戠敓浜嗕互涓嬫儏鍐典箣涓,鍙屾柟琛ㄧ幇涓?
A. 鍙戦佸簲鐢ㄧ▼搴忚涓簊end瀹屼簡10k鏁版嵁,鍏抽棴浜唖ocket: 鍙戦佷富鏈轟綔涓簍cp鐨勪富鍔ㄥ叧闂?榪炴帴灝嗗浜嶧IN_WAIT1鐨勫崐鍏抽棴鐘舵?絳夊緟瀵規柟鐨刟ck),騫朵笖,鍙戦佺紦瀛樹腑鐨?k鏁版嵁騫朵笉娓呴櫎,渚濈劧浼氬彂閫佺粰瀵圭.濡傛灉鎺ユ敹搴旂敤紼嬪簭渚濈劧鍦╮ecv,閭ｄ箞瀹冧細鏀跺埌浣欎笅鐨?k鏁版嵁(榪欎釜鍓嶉鏄?鎺ユ敹绔細鍦ㄥ彂閫佺FIN_WAIT1鐘舵佽秴鏃跺墠鏀跺埌浣欎笅鐨?k鏁版嵁.), 鐒跺悗寰楀埌涓涓绔痵ocket琚叧闂殑娑堟伅(recv榪斿洖0).榪欐椂,搴旇榪涜鍏抽棴.
B. 鍙戦佸簲鐢ㄧ▼搴忓啀嬈¤皟鐢╯end鍙戦?k鐨勬暟鎹? 鍋囧鍙戦佺紦瀛樼殑絀洪棿涓?0k,閭ｄ箞鍙戦佺紦瀛樺彲鐢ㄧ┖闂翠負20-8=12k,澶т簬璇鋒眰鍙戦佺殑8k,鎵浠end鍑芥暟灝嗘暟鎹仛鎷瘋礉鍚?騫剁珛鍗寵繑鍥?192; 鍋囧鍙戦佺紦瀛樼殑絀洪棿涓?2k,閭ｄ箞姝ゆ椂鍙戦佺紦瀛樺彲鐢ㄧ┖闂磋繕鏈?2-8=4k,send()浼氳繑鍥?096,搴旂敤紼嬪簭鍙戠幇榪斿洖鐨勫煎皬浜庤姹傚彂閫佺殑澶у皬鍊煎悗,鍙互璁や負緙撳瓨鍖哄凡婊?榪欐椂蹇呴』闃誨(鎴栭氳繃select絳夊緟涓嬩竴嬈ocket鍙啓鐨勪俊鍙?,濡傛灉搴旂敤紼嬪簭涓嶇悊浼?绔嬪嵆鍐嶆璋冪敤send,閭ｄ箞浼氬緱鍒?1鐨勫? 鍦╨inux涓嬭〃鐜頒負errno=EAGAIN.
C. 鎺ユ敹搴旂敤紼嬪簭鍦ㄥ鐞嗗畬1k鏁版嵁鍚?鍏抽棴浜唖ocket: 鎺ユ敹涓繪満浣滀負涓誨姩鍏抽棴鑰?榪炴帴灝嗗浜嶧IN_WAIT1鐨勫崐鍏抽棴鐘舵?絳夊緟瀵規柟鐨刟ck).鐒跺悗,鍙戦佸簲鐢ㄧ▼搴忎細鏀跺埌socket鍙鐨勪俊鍙?閫氬父鏄?select璋冪敤榪斿洖socket鍙),浣嗗湪璇誨彇鏃朵細鍙戠幇recv鍑芥暟榪斿洖0,榪欐椂搴旇璋冪敤close鍑芥暟鏉ュ叧闂璼ocket(鍙戦佺粰瀵規柟ack); 濡傛灉鍙戦佸簲鐢ㄧ▼搴忔病鏈夊鐞嗚繖涓彲璇葷殑淇″彿,鑰屾槸鍦╯end,閭ｄ箞榪欒鍒嗕袱縐嶆儏鍐墊潵鑰冭檻,鍋囧鏄湪鍙戦佺鏀跺埌RST鏍囧織涔嬪悗璋冪敤send,send灝嗚繑鍥?1,鍚屾椂errno璁句負ECONNRESET琛ㄧず瀵圭緗戠粶宸叉柇寮,浣嗘槸,涔熸湁璇存硶鏄繘紼嬩細鏀跺埌SIGPIPE淇″彿,璇ヤ俊鍙風殑榛樿鍝嶅簲鍔ㄤ綔鏄鍑鴻繘紼?濡傛灉蹇界暐璇ヤ俊鍙?閭ｄ箞send鏄繑鍥?1,errno涓篍PIPE(鏈瘉瀹?;濡傛灉鏄湪鍙戦佺鏀跺埌RST鏍囧織涔嬪墠,鍒檚end鍍忓線甯鎬竴鏍峰伐浣? 浠ヤ笂璇寸殑鏄潪闃誨鐨剆end鎯呭喌,鍋囧send鏄樆濉炶皟鐢?騫朵笖姝ｅソ澶勪簬闃誨鏃?渚嬪涓嬈℃у彂閫佷竴涓法澶х殑buf,瓚呭嚭浜嗗彂閫佺紦瀛?,瀵圭socket鍏抽棴,閭ｄ箞send灝嗚繑鍥炴垚鍔熷彂閫佺殑瀛楄妭鏁?濡傛灉鍐嶆璋冪敤send,閭ｄ箞浼氬悓涓婁竴鏍?
D. 浜ゆ崲鏈烘垨璺敱鍣ㄧ殑緗戠粶鏂紑: 鎺ユ敹搴旂敤紼嬪簭鍦ㄥ鐞嗗畬宸叉敹鍒扮殑1k鏁版嵁鍚?浼氱戶緇粠緙撳瓨鍖鴻鍙栦綑涓嬬殑1k鏁版嵁,鐒跺悗灝辮〃鐜頒負鏃犳暟鎹彲璇葷殑鐜拌薄,榪欑鎯呭喌闇瑕佸簲鐢ㄧ▼搴忔潵澶勭悊瓚呮椂.涓鑸仛娉曟槸璁懼畾涓涓猻elect絳夊緟鐨勬渶澶ф椂闂?濡傛灉瓚呭嚭榪欎釜鏃墮棿渚濈劧娌℃湁鏁版嵁鍙,鍒欒涓簊ocket宸蹭笉鍙敤. 鍙戦佸簲鐢ㄧ▼搴忎細涓嶆柇鐨勫皢浣欎笅鐨勬暟鎹彂閫佸埌緗戠粶涓?浣嗗緇堝緱涓嶅埌紜,鎵浠ョ紦瀛樺尯鐨勫彲鐢ㄧ┖闂存寔緇負0,榪欑鎯呭喌涔熼渶瑕佸簲鐢ㄧ▼搴忔潵澶勭悊. 濡傛灉涓嶇敱搴旂敤紼嬪簭鏉ュ鐞嗚繖縐嶆儏鍐佃秴鏃剁殑鎯呭喌,涔熷彲浠ラ氳繃tcp鍗忚鏈韓鏉ュ鐞?鍏蜂綋鍙互鏌ョ湅sysctl欏逛腑鐨? net.ipv4.tcp_keepalive_intvl net.ipv4.tcp_keepalive_probes net.ipv4.tcp_keepalive_time
Call me Alex 2009-04-13 10:51 鍙戣〃璇勮
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