关于Windows Socket完成端口的问题

最近公司需要编制一个测试WINDOWS Socket 2.x API处理速度的服务器小程序,本人将《WINDOWS网络编程技术》一书中的第八章的服务器例子Chapter08\IOcmplt直接在BCB6.0中编译后，当客户端连接数小于58个时，服务器端不会出错，当大于58时提示两个错：
WSARecv() failed with error 10053
WSARecv() failed with error 10053
Tue Sep 26 00:50:06 2006

当客户端连接大于200时提示：
WSARecv() failed with error 10053
WSARecv() failed with error 10053
Tue Sep 26 00:55:06 2006
GetQueuedCompletionStatus failed with error 995

希望高手指点迷津！！

源码如下：
#include <winsock2.h>
#include <windows.h>
#include <stdio.h>
#include <time.h>

#define PORT 5150
#define DATA_BUFSIZE 8192

#pragma comment(lib, "ws2_32.lib")
#pragma hdrstop

//---------------------------------------------------------------------------

#pragma argsused
typedef struct
{
OVERLAPPED Overlapped;
WSABUF DataBuf;
CHAR Buffer[DATA_BUFSIZE];
DWORD BytesSEND;
DWORD BytesRECV;
} PER_IO_OPERATION_DATA, * LPPER_IO_OPERATION_DATA;


typedef struct
{
SOCKET Socket;
} PER_HANDLE_DATA, * LPPER_HANDLE_DATA;


DWORD WINAPI ServerWorkerThread(LPVOID CompletionPortID);

char str[80];
time_t t;

void main(void)
{
SOCKADDR_IN InternetAddr;
SOCKET Listen;
SOCKET Accept;
HANDLE CompletionPort;
SYSTEM_INFO SystemInfo;
LPPER_HANDLE_DATA PerHandleData;
LPPER_IO_OPERATION_DATA PerIoData;
int i;
DWORD RecvBytes;
DWORD Flags;
DWORD ThreadID;
WSADATA wsaData;
DWORD Ret;



printf("FD_SETSIZE is %d \n", FD_SETSIZE);


if ((Ret = WSAStartup(0x0202, &wsaData)) != 0)
{
printf("WSAStartup failed with error %d\n", Ret);
return;
}

// Setup an I/O completion port.

if ((CompletionPort = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0, 0)) == NULL)
{
printf( "CreateIoCompletionPort failed with error: %d\n", GetLastError());
return;
}

// Determine how many processors are on the system.

GetSystemInfo(&SystemInfo);

// Create worker threads based on the number of processors available on the
// system. Create two worker threads for each processor.

for(i = 0; i < SystemInfo.dwNumberOfProcessors * 2; i++)
{
HANDLE ThreadHandle;

// Create a server worker thread and pass the completion port to the thread.

if ((ThreadHandle = CreateThread(NULL, 0, ServerWorkerThread, CompletionPort,
0, &ThreadID)) == NULL)
{
printf("CreateThread() failed with error %d\n", GetLastError());
return;
}

// Close the thread handle
CloseHandle(ThreadHandle);
}

// Create a listening socket

if ((Listen = WSASocket(AF_INET, SOCK_STREAM, 0, NULL, 0,
WSA_FLAG_OVERLAPPED)) == INVALID_SOCKET)
{
printf("WSASocket() failed with error %d\n", WSAGetLastError());
return;
}

printf("WSASocket() 创建成功... \n");
time(&t);
strcpy(str, asctime(gmtime(&t)));
printf("%s\n", str);

InternetAddr.sin_family = AF_INET;
InternetAddr.sin_addr.s_addr = htonl(INADDR_ANY);
InternetAddr.sin_port = htons(PORT);

if (bind(Listen, (PSOCKADDR) &InternetAddr, sizeof(InternetAddr)) == SOCKET_ERROR)
{
printf("bind() failed with error %d\n", WSAGetLastError());
return;
}

printf("bind() 成功... \n");

// Prepare socket for listening

if (listen(Listen, 500) == SOCKET_ERROR)
{
printf("listen() failed with error %d\n", WSAGetLastError());
return;
}

printf("Agent服务器侦听中 ... \n");

// Accept connections and assign to the completion port.

while(TRUE)
{
if ((Accept = WSAAccept(Listen, NULL, NULL, NULL, 0)) == SOCKET_ERROR)
{
printf("WSAAccept() failed with error %d\n", WSAGetLastError());
return;
}

printf("有客户端连接到Agent服务器 ... \n");

// Create a socket information structure to associate with the socket
if ((PerHandleData = (LPPER_HANDLE_DATA) GlobalAlloc(GPTR,
sizeof(PER_HANDLE_DATA))) == NULL)
{
printf("GlobalAlloc() failed with error %d\n", GetLastError());
return;
}

// Associate the accepted socket with the original completion port.

printf("Socket number %d connected\n", Accept);
PerHandleData->Socket = Accept;

if (CreateIoCompletionPort((HANDLE) Accept, CompletionPort, (DWORD) PerHandleData,
0) == NULL)
{
printf("CreateIoCompletionPort failed with error %d\n", GetLastError());
return;
}

// Create per I/O socket information structure to associate with the
// WSARecv call below.

if ((PerIoData = (LPPER_IO_OPERATION_DATA) GlobalAlloc(GPTR, sizeof(PER_IO_OPERATION_DATA))) == NULL)
{
printf("GlobalAlloc() failed with error %d\n", GetLastError());
return;
}

ZeroMemory(&(PerIoData->Overlapped), sizeof(OVERLAPPED));
PerIoData->BytesSEND = 0;
PerIoData->BytesRECV = 0;
PerIoData->DataBuf.len = DATA_BUFSIZE;
PerIoData->DataBuf.buf = PerIoData->Buffer;

Flags = 0;
if (WSARecv(Accept, &(PerIoData->DataBuf), 1, &RecvBytes, &Flags,
&(PerIoData->Overlapped), NULL) == SOCKET_ERROR)
{
if (WSAGetLastError() != ERROR_IO_PENDING)
{
printf("WSARecv() failed with error %d\n", WSAGetLastError());
return;
}
}
}
}