c++ - IOCP的内存使用情况

Closed. This question is off-topic。它当前不接受答案。
                            
                        
                    
                
                            
                                
                
                        
                            
                        
                    
                        
                            想改善这个问题吗？ Update the question，所以它是on-topic，用于堆栈溢出。
                        
                        2年前关闭。
                                                                                            
                
        
我将代码转换为使用IOCP，并且通信相对稳定，但是应用程序的内存使用量正在增加。看起来我回来了（在完成函数调用时）OverlappedEx的对象比我创建的要少得多。我的代码如下。我究竟做错了什么？

#ifndef NETWORK_DATA
#define NETWORK_DATA

#include <afxwin.h>
#include <vector>
#include <string>
#include "CriticalSectionLocker.h"

using namespace std;

DWORD NetworkManager::NetworkThread(void* param)
{
    bool bRun = true;


    while (bRun)
    {
        DWORD wait = ::WaitForSingleObject(CCommunicationManager::s_hShutdownEvent, 0);
        if (WAIT_OBJECT_0 == wait)
        {
            bRun = false;
            DEBUG_LOG0("Shutdown event was signalled thread");
        }
        else
        {
            DWORD dwBytesTransfered = 0;
            void* lpContext = nullptr;
            OVERLAPPED* pOverlapped = nullptr;

            BOOL bReturn = GetQueuedCompletionStatus(s_IOCompletionPort,
                                                    &dwBytesTransfered,
                                                    (LPDWORD)&lpContext,
                                                    &pOverlapped,
                                                    INFINITE);
            if (nullptr == lpContext)
            {
                DEBUG_LOG0("invalid context");
                /*continue;*/
            }
            else
            {
                if (bReturn && dwBytesTransfered > 0)
                {
                    OverlappedEx* data = reinterpret_cast<OverlappedEx*>(pOverlapped);
                    ServerData* networkData = reinterpret_cast<ServerData*>(lpContext);

                    if (networkData && data)
                    {
                        switch(data->m_opType)
                        {
                        case OverlappedEx::OP_READ:
                                /*DEBUG_LOG4("device name: %s bytes received: %d socket: %d handle: %d",
                                    networkData->Name().c_str(), dwBytesTransfered, networkData->Socket(), networkData->Handle());*/
                                networkData->CompleteReceive(dwBytesTransfered, data);
                                break;
                            case OverlappedEx::OP_WRITE:
                                /*DEBUG_LOG4("device name: %s bytes sent: %d socket: %d handle: %d",
                                    networkData->Name().c_str(), dwBytesTransfered, networkData->Socket(), networkData->Handle());*/
                                networkData->CompleteSend(dwBytesTransfered, data);
                                break;
                        }
                    }
                }
                else
                {
                    /*DEBUG_LOG2("GetQueuedCompletionStatus failed: bReturn: %d dwBytesTransferred: %u", bReturn, dwBytesTransfered);*/
                }
            }
        }
    }
    return 0;
}


enum NetworkType
{
    UDP,
    TCP
};

struct OverlappedEx : public OVERLAPPED
{
    enum OperationType
    {
        OP_READ,
        OP_WRITE
    };

    const static int MAX_PACKET_SIZE = 2048;
    WSABUF m_wBuf;
    char m_buffer[MAX_PACKET_SIZE];
    OperationType m_opType;

    OverlappedEx()
    {
        Clear();
        m_refCount = 1;
    }

    void AddRef()
    {
        ::InterlockedIncrement(&m_refCount);
    }

    void Release()
    {
        ::InterlockedDecrement(&m_refCount);
    }

    int Refcount() const
    {
        return InterlockedExchangeAdd((unsigned long*)&m_refCount, 0UL);
    }

    ~OverlappedEx()
    {
        Clear();
    }

    void Clear()
    {
        memset(m_buffer, 0, MAX_PACKET_SIZE);
        m_wBuf.buf = m_buffer;
        m_wBuf.len = MAX_PACKET_SIZE;
        Internal = 0;
        InternalHigh = 0;
        Offset = 0;
        OffsetHigh = 0;
        hEvent = nullptr;
        m_opType = OP_READ;
    }

private:
    volatile LONG m_refCount;
};


class ServerData
{
public:
    const static int MAX_REVEIVE_QUEUE_SIZE = 100;
    const static int MAX_PACKET_SIZE = 2048;
    const static int MAX_SEND_QUEUE_SIZE = 10;
    const static int MAX_RECEIVE_QUEUE_SIZE = 100;
    const static int MAX_OVERLAPPED_STRUCTS = 20;


    ServerData(NetworkType netType, const string& sName, CCommunicationManager::CommHandle handle,
                            SOCKET sock, HANDLE IOPort) :
        m_sName(sName)
    {
        InitializeCriticalSection(&m_receiveQueLock);
        InitializeCriticalSection(&m_objectLock);
        m_Handle = handle;
        m_Socket = sock;
        m_nIPAddress = 0;
        m_netType = netType;
        m_bEnabled = true;
        m_ovlpIndex = 0;

        for (int i = 0; i < MAX_OVERLAPPED_STRUCTS; ++i)
        {
            m_olps.push_back(new OverlappedEx);
        }

        /* Associate socket with completion handle */
        if (m_Socket != 0)
        {
            CreateIoCompletionPort( reinterpret_cast<HANDLE>(m_Socket), IOPort, reinterpret_cast<ULONG_PTR>(this), 0 );
        }
    }

    ~ServerData()
    {
        CriticalSectionLocker lock(&m_receiveQueLock);
        DeleteCriticalSection(&m_receiveQueLock);

        DeleteCriticalSection(&m_objectLock);
        closesocket(m_Socket);
    }

    const string& Name() const { return m_sName; }
    bool Enabled() const { return m_bEnabled; }
    void SetEnabled(bool bEnabled)
    {
        m_bEnabled = bEnabled;
    }

    int Handle() const { return m_Handle; }
    void SetHandle(int handle)
    {
        m_Handle = handle;
    }

    unsigned long IPAddress() const { return m_nIPAddress; }

    SOCKET Socket() const
    {
        return m_Socket;
    }

    void SetSocket(SOCKET sock)
    {
        m_Socket = sock;
    }

    void SetIPAddress(unsigned long nIP)
    {
        m_nIPAddress = nIP;
    }

    bool ValidTelegram(const vector<char>& telegram) const
    {
        return false;
    }

    OverlappedEx* GetBuffer()
    {
        OverlappedEx* ret = nullptr;

        if (!m_olps.empty())
        {
            ret = m_olps.front();
            m_olps.pop_front();
        }

        return ret;
    }


    void CompleteReceive(size_t numBytes, OverlappedEx* data)
    {
        //DEBUG_LOG1("%d buffers are available", AvailableBufferCount());

        if (numBytes > 0)
        {
            vector<char> v(data->m_buffer, data->m_buffer + numBytes);
            ReceivedData rd;
            rd.SetData(v);
            EnqueReceiveMessage(rd);
        }

        data->Release();
        {
            CriticalSectionLocker lock(&m_objectLock);
            m_olps.push_back(data);
//          DEBUG_LOG1("Queue size: %d", m_olps.size());
        }

        StartReceiving();

    }

    void CompleteSend(size_t numBytes, OverlappedEx* data)
    {

        data->Release();
        {
            CriticalSectionLocker lock(&m_objectLock);
            m_olps.push_back(data);
            //DEBUG_LOG1("Queue size: %d", m_olps.size());
        }

        //DEBUG_LOG2("Object: %s num sent: %d", Name().c_str(), numBytes);
    }

    void StartReceiving()
    {
        DWORD bytesRecv = 0;
        sockaddr_in senderAddr;
        DWORD flags = 0;
        int senderAddrSize = sizeof(senderAddr);
        int rc = 0;

        CriticalSectionLocker lock(&m_objectLock);
        auto olp = GetBuffer();
        if (!olp)
        {
            if (...)
            {
                m_olps.push_back(new OverlappedEx);
                olp = GetBuffer();
            }
            else
            {
                if (...)
                {
                    DEBUG_LOG1("Name: %s ************* NO AVAILABLE BUFFERS - bailing ***************", Name().c_str());
                }
                return;
            }
        }

        olp->Clear();
        olp->m_opType = OverlappedEx::OP_READ;
        olp->AddRef();

        switch(GetNetworkType())
        {
        case UDP:
            {
                rc = WSARecvFrom(Socket(),
                                &olp->m_wBuf,
                                1,
                                &bytesRecv,
                                &flags,
                                (SOCKADDR *)&senderAddr,
                                &senderAddrSize, (OVERLAPPED*)olp, NULL);
            }
            break;
        case TCP:
            {
                rc = WSARecv(Socket(),
                            &olp->m_wBuf,
                            1,
                            &bytesRecv,
                            &flags,
                            (OVERLAPPED*)olp, NULL);
            }
            break;
        }

        if (SOCKET_ERROR == rc)
        {
            DWORD err = WSAGetLastError();
            if (err != WSA_IO_PENDING)
            {
                olp->Release();
                m_olps.push_back(olp);
            }
        }
    }


    void SetWriteBuf(const SendData& msg, OverlappedEx* data)
    {
        int len = min(msg.Data().size(), MAX_PACKET_SIZE);
        memcpy(data->m_buffer, &msg.Data()[0], len);
        data->m_wBuf.buf = data->m_buffer;
        data->m_wBuf.len = len;
    }

    void StartSending(const SendData& msg)
    {

        DEBUG_LOG1("device name: %s", Name().c_str());

        int rc = 0;
        DWORD bytesSent = 0;
        DWORD flags = 0;
        SOCKET sock = Socket();

        int addrSize = sizeof(sockaddr_in);

        CriticalSectionLocker lock(&m_objectLock);
        //UpdateOverlapped(OverlappedEx::OP_WRITE);

        auto olp = GetBuffer();
        if (!olp)
        {
            if (...)
            {
                m_olps.push_back(new OverlappedEx);
                olp = GetBuffer();
                DEBUG_LOG2("name: %s ************* NO AVAILABLE BUFFERS new size: %d ***************", Name().c_str(), m_olps.size());
            }
            else
            {
                if (...)
                {
                    DEBUG_LOG1("Name: %s ************* NO AVAILABLE BUFFERS - bailing ***************", Name().c_str());
                }
                return;
            }
        }

        olp->Clear();
        olp->m_opType = OverlappedEx::OP_WRITE;
        olp->AddRef();
        SetWriteBuf(msg, olp);

        switch(GetNetworkType())
        {
        case UDP:

            rc = WSASendTo(Socket(), &olp->m_wBuf, 1,
                            &bytesSent, flags, (sockaddr*)&msg.SendAddress(),
                            addrSize, (OVERLAPPED*)olp, NULL);
            break;
        case TCP:

            rc = WSASend(Socket(), &olp->m_wBuf, 1,
                        &bytesSent, flags, (OVERLAPPED*)olp, NULL);
            break;
        }

        if (SOCKET_ERROR == rc)
        {
            DWORD err = WSAGetLastError();
            if (err != WSA_IO_PENDING)
            {
                olp->Release();
                m_olps.push_back(olp);
            }
        }
    }

    size_t ReceiveQueueSize()
    {
        CriticalSectionLocker lock(&m_receiveQueLock);
        return m_receiveDataQueue.size();
    }

    void GetAllData(vector <ReceivedData> & data)
    {
        CriticalSectionLocker lock(&m_receiveQueLock);
        while (m_receiveDataQueue.size() > 0)
        {
            data.push_back(m_receiveDataQueue.front());
            m_receiveDataQueue.pop_front();
        }
    }

    void DequeReceiveMessage(ReceivedData& msg)
    {
        CriticalSectionLocker lock(&m_receiveQueLock);
        if (m_receiveDataQueue.size() > 0)
        {
            msg = m_receiveDataQueue.front();
            m_receiveDataQueue.pop_front();
        }
    }

    template <class T>
    void EnqueReceiveMessage(T&& data)
    {
        CriticalSectionLocker lock(&m_receiveQueLock);
        if (m_receiveDataQueue.size() <= MAX_RECEIVE_QUEUE_SIZE)
        {
            m_receiveDataQueue.push_back(data);
        }
        else
        {
            static int s_nLogCount = 0;
            if (s_nLogCount % 100 == 0)
            {
                DEBUG_LOG2("Max queue size was reached handle id: %d in %s", Handle(), Name().c_str());
            }
            s_nLogCount++;
        }
    }

    NetworkType GetNetworkType() const
    {
        return m_netType;
    }

private:
    ServerData(const ServerData&);
    ServerData& operator=(const ServerData&);
private:
    bool m_bEnabled;                                                            //!< This member flags if this reciever is enabled for receiving incoming connections.
    int m_Handle;                                                   //!< This member holds the handle for this receiver.
    SOCKET m_Socket;                                                        //!< This member holds the socket information for this receiver.
    unsigned long m_nIPAddress;                                             //!< This member holds an IP address the socket is bound to.
    deque < ReceivedData > m_receiveDataQueue;
    CRITICAL_SECTION m_receiveQueLock;
    CRITICAL_SECTION m_objectLock;
    string m_sName;
    NetworkType m_netType;
    deque<OverlappedEx*> m_olps;
    size_t m_ovlpIndex;
};


#endif

最佳答案

您对void Release()的实现没有任何意义-您减少m_refCount怎么办？一定是

void Release()
{
    if (!InterlockedDecrement(&m_refCount)) delete this;
}

结果，您永远不会释放OverlappedEx* data-这只是我所查看的，这会导致内存泄漏。

也可以建议-使用WaitForSingleObject(CCommunicationManager::s_hShutdownEvent, 0);这对于检测关机是个坏主意。仅调用GetQueuedCompletionStatus并进行关机调用PostQueuedCompletionStatus(s_IOCompletionPort, 0, 0, 0)多次（数量或线程在s_IOCompletionPort上监听），并且如果线程视图pOverlapped==0-则退出。

采用

OverlappedEx* data = static_cast<OverlappedEx*>(pOverlapped);

代替reinterpret_cast

make ~OverlappedEx() private-不能直接调用，只能通过Release

            olp->Release();
            m_olps.push_back(olp);

在对象上调用Release()后，您不能在此处对其进行更多访问，所以不能访问olp->Release()或m_olps.push_back(olp);，但不能同时访问两者。这会杀死Release的所有逻辑，可能是您需要覆盖operator delete的OverlappedEx并在其中调用m_olps.push_back(olp);，当然也覆盖operator new

再次(OVERLAPPED*)olp-这里的reinterpret_cast是什么？因为您从OVERLAPPED编译器自动继承了自己的结构，所以请在此处进行类型转换

关于c++ - IOCP的内存使用情况，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/44809948/