最近测试，发现交易有时成功有时超时，这两天查询总结发现现状如下：
客户端：在异地，通过专线连到我方服务器（双方不同网段）
客户端系统：XP
服务端系统：linux
现状：
1. 只要客户端发的字符串中连续空格过多时，服务器端recv接收信息时就要好几秒（是通过recv后的时间减去accept后的时间得出消耗的时间。发连续40个空格时不到1秒，80个空格时要8秒，200多空格时要几十秒）；
2. 如果发的不是连续空格，哪怕是几千个字节也是秒收秒回一秒内搞定；
3. 如果在内网同网段收发，哪怕多少个空格也是一秒内搞定，不会超时。
现在怀疑是不是网络设置哪里有问题，又或者是网络设备问题，但网络工作人员也没查到什么异常。不知各位有没有碰到类似情况，麻烦各位了
（由于担心是应用系统的问题，我是单独写了很简单的socket客户端和服务器端来测试，因此不会涉及系统应用逻辑问题。）
测试服务端日志情况：
第一笔70个长度，中间4个空格，秒杀
第二笔101个长度，中间有40个空格，秒杀
第三笔141个长度，中间有80个空格，接收信息就用时8秒
/usr/xxx/tmp 1259> ./a.out
socket created .
socked id: 3
connected.
local port:3995
listening...
Fri Jun 20 15:59:30 2014
[7096]accept a new connection:4[162.61.12.29]
Fri Jun 20 15:59:30 2014
[7098]收到消息: [70][0001AINQ0222000100000000000000000000000O0619161641000028021 1]
send OK
goto END
Fri Jun 20 16:00:57 2014
[7096]accept a new connection:4[162.61.12.29]
Fri Jun 20 16:00:57 2014
[7102]收到消息: [101][0001AINQ0222000100000000000000000000000O0619161641000028021 40]
send OK
goto END
Fri Jun 20 16:01:43 2014
[7096]accept a new connection:4[162.61.12.29]
Fri Jun 20 16:01:51 2014
[7105]收到消息: [141][0001AINQ0222000100000000000000000000000O0619161641000028021 80]
send OK
goto END
socket客户端（XP下的VC程序）如下：
#include <stdio.h>
#include<WINSOCK2.H>
#pragma comment(lib,"ws2_32.lib")
#define PORT 3995
#define REMOTE_IP "163.1.8.128"
int main(int argc,char *argv[])
{
int s ,iRcv=0;
struct sockaddr_in addr ;
char mybuffer[1024];
WSADATA wsaData = {0};
if(WSAStartup(MAKEWORD(2, 2), &wsaData) != 0)
{
printf("WSAStartup failed.\n");
exit(-1);
}
if( (s=socket(AF_INET,SOCK_STREAM,0))<0 ) /*建立一个socket。*/
{
perror("socket");
printf("socket err [%d][%d]\n", s, WSAGetLastError());
exit(1);
}
else
{
printf("socket created .\n");
printf("socked id: %d \n",s);
}
memset(&addr, 0, sizeof(addr)); /*设置addr的信息。*/
addr.sin_family =AF_INET;
addr.sin_port=htons(PORT);
addr.sin_addr.s_addr=inet_addr(REMOTE_IP);
if(connect(s,&addr,sizeof(addr))<0) /*连接到远程服务器。*/
{
perror("connect");
printf("socket err [%d][%d]\n", s, WSAGetLastError());
close(s);
exit(1);
}
else /*输出信息。*/
{
printf("connected ok!\n");
printf("remote ip:%s\n",REMOTE_IP);
printf("remote port:%d\n",PORT);
}
strcpy(mybuffer, "0001AINQ0222000100000000000000000000000O0619161641000028021 030000005000100000000000021000000 62135600104000018008113EA0");
if(-1 == send(s, mybuffer, strlen(mybuffer), 0))
{
printf("send err!!!\n");
close(s);
exit(-1);
}
printf("send ok \n");
if(-1 == (iRcv = recv(s, mybuffer, sizeof(mybuffer), 0)))
{
printf("recv err!!!\n");
close(s);
exit(-1);
}
else
{
printf("[%d]收到消息: [%d][%s]\n", getpid(), iRcv, mybuffer);
}
getch();
close(s);
return 0;
}
socket服务端（Linux）如下：
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <errno.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <signal.h>
#include <time.h>
#define IPADDR "127.0.0.1"
#define PORT 3995
#define MAX 10
int main()
{
int iSocket, iSocket2, iRet, iAddrLen;
int iRcv=0;
char szBuf[2048];
struct sockaddr_in stAddr;
const int reuse = 1;
struct tm *ptr;
time_t loctime;
signal(SIGCLD,SIG_IGN);
if((iSocket = socket(AF_INET, SOCK_STREAM, 0)) < 0)
{
printf("socket err!\n");
exit(-1);
}
else
{
printf("socket created .\n");
printf("socked id: %d \n",iSocket);
}
if(iRet = setsockopt(iSocket, SOL_SOCKET, SO_REUSEADDR, (const char*)&reuse, sizeof(reuse)))
{
printf("setsockopt err![%d][%d]\n", iRet, errno);
close(iSocket);
exit(-1);
}
memset(&stAddr, 0, sizeof(stAddr));
stAddr.sin_family =AF_INET;
stAddr.sin_port = htons(PORT);
stAddr.sin_addr.s_addr = htonl(INADDR_ANY);
if((iRet = bind(iSocket, &stAddr, sizeof(stAddr))) < 0)
{
printf("bind err![%d][%d]\n", iRet, errno);
close(iSocket);
exit(-1);
}
else
{
printf("connected.\n");
printf("local port:%d\n",PORT) ;
}
if((iRet = listen(iSocket, 3)) < 0)
{
printf("listen err![%d]\n", iRet);
goto ERR;
}
else
{
printf("listening...\n");
}
iAddrLen = sizeof(stAddr);
while(1)
{
if((iSocket2 = accept(iSocket, &stAddr, &iAddrLen)) < 0)
{
printf("accept err![%d][%d][%s]\n", iSocket2, errno, strerror(errno));
goto ERR;
}
else
{
loctime=time(NULL);
ptr=localtime(&loctime);
printf(asctime(ptr));
printf("[%d]accept a new connection:%d[%s]\n", getpid(), iSocket2, inet_ntoa(stAddr.sin_addr));
}
if((iRet = fork()) < 0)
{
printf("fork err! \n");
goto ERR;
}
else if(iRet > 0)
{
// printf("Let Son To Recieve It,I Continue To accept\n");
close(iSocket2);
continue;
}
memset(szBuf, 0, sizeof(szBuf));
if(-1 == (iRcv = recv(iSocket2, szBuf, sizeof(szBuf), 0)))
{
printf("recv err!!![%d][%s]\n", errno, strerror(errno));
goto ERR;
}
else
{
loctime=time(NULL);
ptr=localtime(&loctime);
printf(asctime(ptr));
printf("[%d]收到消息: [%d][%s]\n", getpid(), iRcv, szBuf);
}
memset(szBuf, 0, sizeof(szBuf));
strcpy(szBuf, "快点好吧，受不了啦");
if(-1 == send(iSocket2, szBuf, strlen(szBuf), 0))
{
printf("send err!!!\n");
goto ERR;
}
else
{
printf("send OK\n");
}
goto END;
}
ERR:
close(iSocket);
close(iSocket2);
printf("server ERR\n");
return -123;
END:
close(iSocket);
close(iSocket2);
printf("goto END\n");
return 0;
}
