QUdpSocket接收效率问题

[SherlockThang]

在未设置QAbstractSocket::ReceiveBufferSizeSocketOption，会出现丢帧的情况，设置了，数据会出现大量的积压。发送端每次发送1k字节，发送时间间隔约30us，发送10000次，经测试数据会出现严重积压。数据发送完了，接收端依然在接收数据，达不到项目需要实施接收的目的。

udpclient::udpclient(QObject *parent) : QThread(parent)
{
}

void udpclient::setNetwork(const char *IPstr, quint16 port)
{
    bool bindvalue = false;
    if (strcmp(IPstr, "") == 1) {
        bindvalue = pQUdpSocket->bind (port, QAbstractSocket::ShareAddress | QAbstractSocket::ReuseAddressHint);   //建立监听
        qDebug("Type 2: %d", bindvalue);
    } else {
        bindvalue = pQUdpSocket->bind (QHostAddress(IPstr), port, QAbstractSocket::ShareAddress | QAbstractSocket::ReuseAddressHint);   //建立监听
        qDebug("Type 2: %d", bindvalue);
    }
}

void udpclient::setMCNetwork(QString IPstr, quint16 port)
{
    if (!IPstr.isEmpty ()) {
        qDebug() << "MC Bind:" << port << "\t" << pQUdpSocket->bind (QHostAddress::AnyIPv4, port, (QAbstractSocket::ShareAddress | QAbstractSocket::ReuseAddressHint));
        pQUdpSocket->setSocketOption (QAbstractSocket::MulticastLoopbackOption, 1);//禁止接收本地回传
        qDebug() << "Join Group:" << IPstr << "\t" << pQUdpSocket->joinMulticastGroup (QHostAddress (IPstr));
        pQUdpSocket->setSocketOption (QAbstractSocket::ReceiveBufferSizeSocketOption, 0xFFFFFFFF);
        pQUdpSocket->setSocketOption (QAbstractSocket::SendBufferSizeSocketOption, 0xFFFFFFFF);
    } else {
        pQUdpSocket->bind (QHostAddress(IPstr), port, QAbstractSocket::ShareAddress | QAbstractSocket::ReuseAddressHint);   //建立监听
    }
}

void udpclient::processPendingDatagrams()
{
    QByteArray datagram;
    while(pQUdpSocket->hasPendingDatagrams()) {
        datagram.resize(pQUdpSocket->pendingDatagramSize());
        pQUdpSocket->readDatagram(datagram.data(), datagram.size());  //接收数据

        QMutexLocker locker(&mMutex); // 锁定队列对象，禁止同时操作
        if(mPool.size() > 0xFFFF){ // 当队列大于限定值时，
            mPool.removeFirst ();
        }
        RxSum ++;
        mPool.enqueue (datagram);
        queueWait.wakeOne ();
    }
}

void udpclient::run()
{
    pQUdpSocket = new QUdpSocket();
    RxSum = TxSum = 0;
    setMCNetwork ("239.192.43.78", 4378);
    forever {
        QByteArray datagram;
        while(pQUdpSocket->hasPendingDatagrams()) {
            datagram.resize(pQUdpSocket->pendingDatagramSize());
            pQUdpSocket->readDatagram(datagram.data(), datagram.size());  //接收数据
            RxSum ++;
            qDebug("Qt Read num : %u", RxSum);
        }
        msleep(1);
    }
}

[赵4老师]

仅供参考：

//循环向a函数每次发送200个字节长度（这个是固定的）的buffer,
//a函数中需要将循环传进来的buffer，组成240字节（也是固定的）的新buffer进行处理，
//在处理的时候每次从新buffer中取两个字节打印
#ifdef _MSC_VER
    #pragma warning(disable:4996)
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef _MSC_VER
    #include <windows.h>
    #include <process.h>
    #include <io.h>
    #define  MYVOID             void
    #define  vsnprintf          _vsnprintf
#else
    #include <unistd.h>
    #include <sys/time.h>
    #include <pthread.h>
    #define  CRITICAL_SECTION   pthread_mutex_t
    #define  MYVOID             void *
#endif
//Log{
#define MAXLOGSIZE 20000000
#define MAXLINSIZE 16000
#include <time.h>
#include <sys/timeb.h>
#include <stdarg.h>
char logfilename1[]="MyLog1.log";
char logfilename2[]="MyLog2.log";
static char logstr[MAXLINSIZE+1];
char datestr[16];
char timestr[16];
char mss[4];
CRITICAL_SECTION cs_log;
FILE *flog;
#ifdef _MSC_VER
void Lock(CRITICAL_SECTION *l) {
    EnterCriticalSection(l);
}
void Unlock(CRITICAL_SECTION *l) {
    LeaveCriticalSection(l);
}
void sleep_ms(int ms) {
    Sleep(ms);
}
#else
void Lock(CRITICAL_SECTION *l) {
    pthread_mutex_lock(l);
}
void Unlock(CRITICAL_SECTION *l) {
    pthread_mutex_unlock(l);
}
void sleep_ms(int ms) {
    usleep(ms*1000);
}
#endif
void LogV(const char *pszFmt,va_list argp) {
    struct tm *now;
    struct timeb tb;

    if (NULL==pszFmt||0==pszFmt[0]) return;
    vsnprintf(logstr,MAXLINSIZE,pszFmt,argp);
    ftime(&tb);
    now=localtime(&tb.time);
    sprintf(datestr,"%04d-%02d-%02d",now->tm_year+1900,now->tm_mon+1,now->tm_mday);
    sprintf(timestr,"%02d:%02d:%02d",now->tm_hour     ,now->tm_min  ,now->tm_sec );
    sprintf(mss,"%03d",tb.millitm);
    printf("%s %s.%s %s",datestr,timestr,mss,logstr);
    flog=fopen(logfilename1,"a");
    if (NULL!=flog) {
        fprintf(flog,"%s %s.%s %s",datestr,timestr,mss,logstr);
        if (ftell(flog)>MAXLOGSIZE) {
            fclose(flog);
            if (rename(logfilename1,logfilename2)) {
                remove(logfilename2);
                rename(logfilename1,logfilename2);
            }
        } else {
            fclose(flog);
        }
    }
}
void Log(const char *pszFmt,...) {
    va_list argp;

    Lock(&cs_log);
    va_start(argp,pszFmt);
    LogV(pszFmt,argp);
    va_end(argp);
    Unlock(&cs_log);
}
//Log}
#define ASIZE    200
#define BSIZE    240
#define CSIZE      2
char Abuf[ASIZE];
char Cbuf[CSIZE];
CRITICAL_SECTION cs_HEX;
CRITICAL_SECTION cs_BBB;
struct FIFO_BUFFER {
    int  head;
    int  tail;
    int  size;
    char data[BSIZE];
} BBB;
int No_Loop=0;
void HexDump(int cn,char *buf,int len) {
    int i,j,k;
    char binstr[80];

    Lock(&cs_HEX);
    for (i=0;i<len;i++) {
        if (0==(i%16)) {
            sprintf(binstr,"%03d %04x -",cn,i);
            sprintf(binstr,"%s %02x",binstr,(unsigned char)buf[i]);
        } else if (15==(i%16)) {
            sprintf(binstr,"%s %02x",binstr,(unsigned char)buf[i]);
            sprintf(binstr,"%s  ",binstr);
            for (j=i-15;j<=i;j++) {
                sprintf(binstr,"%s%c",binstr,('!'<buf[j]&&buf[j]<='~')?buf[j]:'.');
            }
            Log("%s\n",binstr);
        } else {
            sprintf(binstr,"%s %02x",binstr,(unsigned char)buf[i]);
        }
    }
    if (0!=(i%16)) {
        k=16-(i%16);
        for (j=0;j<k;j++) {
            sprintf(binstr,"%s   ",binstr);
        }
        sprintf(binstr,"%s  ",binstr);
        k=16-k;
        for (j=i-k;j<i;j++) {
            sprintf(binstr,"%s%c",binstr,('!'<buf[j]&&buf[j]<='~')?buf[j]:'.');
        }
        Log("%s\n",binstr);
    }
    Unlock(&cs_HEX);
}
int GetFromRBuf(int cn,CRITICAL_SECTION *cs,struct FIFO_BUFFER *fbuf,char *buf,int len) {
    int lent,len1,len2;

    lent=0;
    Lock(cs);
    if (fbuf->size>=len) {
        lent=len;
        if (fbuf->head+lent>BSIZE) {
            len1=BSIZE-fbuf->head;
            memcpy(buf     ,fbuf->data+fbuf->head,len1);
            len2=lent-len1;
            memcpy(buf+len1,fbuf->data           ,len2);
            fbuf->head=len2;
        } else {
            memcpy(buf     ,fbuf->data+fbuf->head,lent);
            fbuf->head+=lent;
        }
        fbuf->size-=lent;
    }
    Unlock(cs);
    return lent;
}
MYVOID thdB(void *pcn) {
    char        *recv_buf;
    int          recv_nbytes;
    int          cn;
    int          wc;
    int          pb;

    cn=(int)pcn;
    Log("%03d thdB              thread begin...\n",cn);
    while (1) {
        sleep_ms(10);
        recv_buf=(char *)Cbuf;
        recv_nbytes=CSIZE;
        wc=0;
        while (1) {
            pb=GetFromRBuf(cn,&cs_BBB,&BBB,recv_buf,recv_nbytes);
            if (pb) {
                Log("%03d recv %d bytes\n",cn,pb);
                HexDump(cn,recv_buf,pb);
                sleep_ms(1);
            } else {
                sleep_ms(1000);
            }
            if (No_Loop) break;//
            wc++;
            if (wc>3600) Log("%03d %d==wc>3600!\n",cn,wc);
        }
        if (No_Loop) break;//
    }
#ifndef _MSC_VER
    pthread_exit(NULL);
#endif
}
int PutToRBuf(int cn,CRITICAL_SECTION *cs,struct FIFO_BUFFER *fbuf,char *buf,int len) {
    int lent,len1,len2;

    Lock(cs);
    lent=len;
    if (fbuf->size+lent>BSIZE) {
        lent=BSIZE-fbuf->size;
    }
    if (fbuf->tail+lent>BSIZE) {
        len1=BSIZE-fbuf->tail;
        memcpy(fbuf->data+fbuf->tail,buf     ,len1);
        len2=lent-len1;
        memcpy(fbuf->data           ,buf+len1,len2);
        fbuf->tail=len2;
    } else {
        memcpy(fbuf->data+fbuf->tail,buf     ,lent);
        fbuf->tail+=lent;
    }
    fbuf->size+=lent;
    Unlock(cs);
    return lent;
}
MYVOID thdA(void *pcn) {
    char        *send_buf;
    int          send_nbytes;
    int          cn;
    int          wc;
    int           a;
    int          pa;

    cn=(int)pcn;
    Log("%03d thdA              thread begin...\n",cn);
    a=0;
    while (1) {
        sleep_ms(100);
        memset(Abuf,a,ASIZE);
        a=(a+1)%256;
        if (16==a) {No_Loop=1;break;}//去掉这句可以让程序一直循环直到按Ctrl+C或Ctrl+Break或当前目录下存在文件No_Loop
        send_buf=(char *)Abuf;
        send_nbytes=ASIZE;
        Log("%03d sending %d bytes\n",cn,send_nbytes);
        HexDump(cn,send_buf,send_nbytes);
        wc=0;
        while (1) {
            pa=PutToRBuf(cn,&cs_BBB,&BBB,send_buf,send_nbytes);
            Log("%03d sent %d bytes\n",cn,pa);
            HexDump(cn,send_buf,pa);
            send_buf+=pa;
            send_nbytes-=pa;
            if (send_nbytes<=0) break;//
            sleep_ms(1000);
            if (No_Loop) break;//
            wc++;
            if (wc>3600) Log("%03d %d==wc>3600!\n",cn,wc);
        }
        if (No_Loop) break;//
    }
#ifndef _MSC_VER
    pthread_exit(NULL);
#endif
}
int main() {
#ifdef _MSC_VER
    InitializeCriticalSection(&cs_log);
    InitializeCriticalSection(&cs_HEX);
    InitializeCriticalSection(&cs_BBB);
#else
    pthread_t threads[2];
    int threadsN;
    int rc;
    pthread_mutex_init(&cs_log,NULL);
    pthread_mutex_init(&cs_HEX,NULL);
    pthread_mutex_init(&cs_BBB,NULL);
#endif
    Log("Start===========================================================\n");

    BBB.head=0;
    BBB.tail=0;
    BBB.size=0;

#ifdef _MSC_VER
    _beginthread((void(__cdecl *)(void *))thdA,0,(void *)1);
    _beginthread((void(__cdecl *)(void *))thdB,0,(void *)2);
#else
    threadsN=0;
    rc=pthread_create(&(threads[threadsN++]),NULL,thdA,(void *)1);if (rc) Log("%d=pthread_create %d error!\n",rc,threadsN-1);
    rc=pthread_create(&(threads[threadsN++]),NULL,thdB,(void *)2);if (rc) Log("%d=pthread_create %d error!\n",rc,threadsN-1);
#endif

    if (!access("No_Loop",0)) {
        remove("No_Loop");
        if (!access("No_Loop",0)) {
            No_Loop=1;
        }
    }
    while (1) {
        sleep_ms(1000);
        if (No_Loop) break;//
        if (!access("No_Loop",0)) {
            No_Loop=1;
        }
    }
    sleep_ms(3000);
    Log("End=============================================================\n");
#ifdef _MSC_VER
    DeleteCriticalSection(&cs_BBB);
    DeleteCriticalSection(&cs_HEX);
    DeleteCriticalSection(&cs_log);
#else
    pthread_mutex_destroy(&cs_BBB);
    pthread_mutex_destroy(&cs_HEX);
    pthread_mutex_destroy(&cs_log);
#endif
    return 0;
}

任何收发两端速度不一致的通讯，都需要在它们之间使用一个足够大的FIFO缓冲区。 对任何FIFO缓冲区的使用，都需要仔细考虑接收端接收时超时无数据和发送端发送时FIFO缓冲区已满这两种情况下该如何做。 这些概念都在这段经典代码中有所体现。 这段经典代码还包括以下必须考虑的因素： ◆跨Windows和Linux平台 ◆多线程锁 ◆多线程日志 ◆日志文件占用的磁盘空间可控 ◆日志中的时间包括毫秒 ◆传输的数据对应的每个字节到底是几 ◆如何退出多线程程序 ◆……

[SherlockThang]

谢谢，Qt封装的，除了发送效率还可以，接收的压根不行，自己用Windows下的winsocket封装了，效果还不错。估计linux下也得用系统自带的socket封装了。跨平台的好用，在低速情况下没问题，高速的情况下就不行了。

    char buf[MSGBUFSIZE];
    sockaddr_in recver_addr;
    int  addrlen;

struct NetworkCfg {
    u32 RxIP;
    u16 RxPort;
    u32 TxIP;
    u16 TxPort;
    bool isMC;//Multicast
    bool isBlock;//堵塞
    bool isLoop;//回传
    bool isReuse;//端口重用
    short TTL;//电平0-255
    int RxBufSize;//接收缓存大小
    int TxBufSize;//发送缓存大小
    int RxTimeOut;//接收时延
    int TxTimeOut;//发送时延
};

bool slotInitMCNetUDP(NetworkCfg mcfg)
 bool pass = true;
    //初始化套接字
    WSADATA wsaData; //Version Info
    // Initialize Windows socket library
    if(WSAStartup(MAKEWORD(2,2), &wsaData) != 0) {
        printf("init socket failure! at:%s Line: %d\n", __FILE__, __LINE__);
        pass = false;
    }

    pGloblePara->mUDPSocket = socket (AF_INET, SOCK_DGRAM, IPPROTO_IP);
    if(pass && INVALID_SOCKET == pGloblePara->mUDPSocket){
        printf("Error : %d at:%s Line: %d\n", WSAGetLastError(), __FILE__, __LINE__);
        pass = false;
    }

    //设置端口重用
    u_int i_val = 1;
    if (false == mcfg.isReuse) {
        i_val = 0;
    }
    if(pass && SOCKET_ERROR == setsockopt(pGloblePara->mUDPSocket, SOL_SOCKET, SO_REUSEADDR, (char *)&i_val, sizeof(u_int))){
        printf("Error : %d at:%s Line: %d\n", WSAGetLastError(), __FILE__, __LINE__);
        pass = false;
    }

    //设置组播
    sockaddr_in recver_addr;
    memset(&recver_addr, 0, sizeof (sockaddr_in));
    recver_addr.sin_family       = AF_INET;
    recver_addr.sin_addr.s_addr  = htonl (mcfg.isMC ? INADDR_ANY : mcfg.RxIP);//如果是组播则绑定ANY,否则绑定给定的地址
    recver_addr.sin_port         = htons (mcfg.RxPort);
    //    printf ("MC : %d \n" ,mcfg.isMC);
    if(pass && SOCKET_ERROR == bind (pGloblePara->mUDPSocket, (struct sockaddr *)&recver_addr, sizeof(recver_addr))) {
        printf("Error : %d at:%s Line: %d\n", WSAGetLastError(), __FILE__, __LINE__);
        pass = false;
    }

    if (pass && true == mcfg.isMC) {
        mMultiCast.imr_multiaddr.s_addr = htonl(mcfg.RxIP);//inet_addr //组播地址
        mMultiCast.imr_interface.s_addr = htonl(INADDR_ANY);

        if(pass && SOCKET_ERROR == setsockopt (pGloblePara->mUDPSocket, IPPROTO_IP, IP_ADD_MEMBERSHIP, (char *)&mMultiCast, sizeof(mMultiCast))) {
            printf("Error : %d at:%s Line: %d\n", WSAGetLastError(), __FILE__, __LINE__);
            pass = false;
        }
    }

    //阻塞设置
    if (false == mcfg.isBlock) {
        u_long iMode = 1;//如允许非阻塞模式则非零，如禁止非阻塞模式则为零, 默认0，阻塞
        ioctlsocket(pGloblePara->mUDPSocket, FIONBIO, &iMode); //设置阻塞
    }

    //数据回传设置
    int loop = 1;//允许回传
    if (false == mcfg.isLoop) {
        loop = 0;//禁用回传
    }
    if (pass && SOCKET_ERROR == setsockopt(pGloblePara->mUDPSocket, IPPROTO_IP, IP_MULTICAST_LOOP, (char*)&loop, sizeof(int))) {
        printf("Error : %d at:%s Line: %d\n", WSAGetLastError(), __FILE__, __LINE__);
        pass = false;
    }

    //电平设置
    if (pass && 0 <= mcfg.TTL) {
        int optval = mcfg.TTL;
        if(SOCKET_ERROR == setsockopt(pGloblePara->mUDPSocket, IPPROTO_IP, IP_MULTICAST_TTL, (char*)&optval, sizeof(int))) {
            printf("Error : %d at:%s Line: %d\n", WSAGetLastError(), __FILE__, __LINE__);
            pass = false;
        }
    }

    if (pass && 0 <= mcfg.RxBufSize) {
        int nZero = mcfg.RxBufSize;//设置接收缓存大小
        if (SOCKET_ERROR == setsockopt(pGloblePara->mUDPSocket, SOL_SOCKET, SO_RCVBUF, (char *)&nZero, sizeof(int))) {
            printf("Error : %d at:%s Line: %d\n", WSAGetLastError(), __FILE__, __LINE__);
            pass = false;
        }
    }

    if (pass && 0 <= mcfg.TxBufSize) {
        int nZero = mcfg.TxBufSize;//设置发送缓存大小
        //⒌在发送数据的时，不执行由系统缓冲区到socket缓冲区的拷贝，以提高程序的性能
        if (SOCKET_ERROR == setsockopt(pGloblePara->mUDPSocket, SOL_SOCKET, SO_SNDBUF, (char *)&nZero, sizeof(int))) {
            printf("Error : %d at:%s Line: %d\n", WSAGetLastError(), __FILE__, __LINE__);
            pass = false;
        }
    }

    if (pass && 0 <= mcfg.RxTimeOut) {
        int nNetTimeout = mcfg.RxTimeOut; //1秒 本地可能sendto不出去数据，然后recvfrom就会被阻塞，这时就需要设置 这两个参数的值提高程序质量,设置接收阻塞时长
        if (SOCKET_ERROR == setsockopt(pGloblePara->mUDPSocket, SOL_SOCKET, SO_RCVTIMEO, (char *)&nNetTimeout, sizeof(int))) {
            printf("Error : %d at:%s Line: %d\n", WSAGetLastError(), __FILE__, __LINE__);
            pass = false;
        }
    }

    if (pass && 0 <= mcfg.TxTimeOut) {
        int nNetTimeout = mcfg.TxTimeOut; //1秒 本地可能sendto不出去数据，然后recvfrom就会被阻塞，这时就需要设置 这两个参数的值提高程序质量,设置接收阻塞时长
        if (SOCKET_ERROR == setsockopt(pGloblePara->mUDPSocket, SOL_SOCKET, SO_SNDTIMEO, (char *)&nNetTimeout, sizeof(int))) {
            printf("Error : %d at:%s Line: %d\n", WSAGetLastError(), __FILE__, __LINE__);
            pass = false;
        }
    }
    return pass;
}
recv (pGloblePara->mUDPSocket, buf, MSGBUFSIZE, 0);