一个简单的进程池实现

实在很简陋，许多控制功能都没有实现：）
不过也能表现大致的框架吧。

/* * A simple process pool */#include <iostream>#include <queue>#include <vector>#include <algorithm> #include <sys/wait.h>#include <assert.h>#include <stdlib.h>#include <unistd.h>#include <signal.h> #include <sys/mman.h>#include <sys/select.h> using namespace std; int iProcessCount = 0;int *pDispatchCount; void InterruptHanler(int iSigno){//ToDo: kill all childrencerr << "Dispatch Count: " << endl;for( unsigned int i = 0; i < iProcessCount; i++ ){cerr << i << "\t" << pDispatchCount[i] << endl;}exit(0);} //ToDo: replace two pipes with socketpairint main(int argc, char **argv){if( argc == 2 ){iProcessCount = atoi(argv[1]);} if( iProcessCount <= 0 )iProcessCount = 10; int (*iPipeFD)[2] = new(int[iProcessCount][2]);int (*iNotifyPipeFD)[2] = new(int[iProcessCount][2]);;pDispatchCount = (int *)mmap(0, sizeof(int) * iProcessCount, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0); queue<int> queIdle;vector<int> vecBusy; for( unsigned int i = 0; i < iProcessCount; i++ ){if( pipe(iPipeFD[i]) == -1 ){cerr << "pipe error" << endl;return 0;} if( pipe(iNotifyPipeFD[i]) == -1 ){cerr << "pipe error" << endl;return 0;}} for( unsigned int i = 0; i < iProcessCount; i++ ){pid_t pid = fork();if( pid < 0 ){cerr << "fork error" << endl;return 0;} if( pid == 0 )//child{int iCount = 0;while(1){char sBuf[16] = {0};read( iPipeFD[i][0], sBuf, 15 );cout << i << ": " << getpid() << ", " << ++iCount << "\t" << sBuf << endl;pDispatchCount[i]++; //Do your work hereint iMax = atoi(sBuf);usleep(iMax % 10000); write( iNotifyPipeFD[i][1], "1", 1);}} queIdle.push(i);} signal( SIGINT, InterruptHanler ); int iCounter = 0;while( 1 ) {if( queIdle.size() ){//Dispatch workchar sBuf[16] = {0};int iRand = rand();snprintf(sBuf, 16, "%d", iRand); int iIndex = queIdle.front();queIdle.pop();write( iPipeFD[iIndex][1], sBuf, strlen(sBuf) );cout << "dispatch " << sBuf << " to " << iIndex << endl; vecBusy.push_back(iIndex);} cout << ++iCounter << "\t: queIdle.size = " << queIdle.size() << " vecBusy.size = " << vecBusy.size() << endl;//if( vecBusy.size() ){fd_set set;FD_ZERO(&set); int iMaxFD = 0;for( unsigned int i = 0; i < vecBusy.size(); i++ ){int iIndex = vecBusy[i];FD_SET( iNotifyPipeFD[iIndex][0], &set);iMaxFD = max( iMaxFD, iNotifyPipeFD[iIndex][0]);} struct timeval timeout;timeout.tv_sec = 1;timeout.tv_usec = 0;select(iMaxFD + 1, &set, NULL, NULL, &timeout); for( vector<int>::iterator it = vecBusy.begin(); it != vecBusy.end(); ){int iIndex = *it;int iReadFD = iNotifyPipeFD[iIndex][0];if( FD_ISSET( iReadFD, &set ) ){queIdle.push(iIndex);it = vecBusy.erase(it);}else{it++;}}}} return 0;}

http://icomes.net/2009/10/11/%E4%B8%80%E4%B8%AA%E7%AE%80%E5%8D%95%E7%9A%84%E8%BF%9B%E7%A8%8B%E6%B1%A0%E5%AE%9E%E7%8E%B0/