Qprocess启动的mpi程序如何清晰kill？

Question

我有一个pyqt程序，需要运行一个外部mpi程序。我使用 Qprocess 启动 mpi 程序。但是，我发现当我调用 kill 方法终止 mpi 程序时，mpi 进程仍在运行。有谁知道如何清楚地杀死 Qprocess 启动的 mpi 程序？

下面是我的测试程序：

test.py

import sys
from PyQt5 import QtCore, QtWidgets
from PyQt5.QtCore import pyqtSignal, QThread, QProcess
from PyQt5.QtWidgets import QApplication, QWidget
from PyQt5.QtGui import QTextCursor

class worker(QThread):
    logChange = pyqtSignal(str)

    def __init__(self):
        super().__init__()

    def run(self):
        process = QProcess()
        command = f"mpiexec -n 8 test_mpi.exe"
        process.start(command)
        process.waitForStarted()
        self.stopFlag = False
        while True:
            if self.stopFlag:
                process.kill()
                process.waitForFinished(-1)
                self.logChange.emit("STOP!\n")
                break

            if process.waitForReadyRead(1000):
                output = process.readAllStandardOutput()
                output = bytearray(output).decode("gbk")
                self.logChange.emit(output)
            else:
                QApplication.processEvents()
                if process.state() == 0:
                    self.logChange.emit("FINISHED!\n")
                    break

    def stop(self):
        self.stopFlag = True

class Ui_Form(object):
    def setupUi(self, Form):
        Form.setObjectName("Form")
        Form.resize(400, 300)
        self.verticalLayout = QtWidgets.QVBoxLayout(Form)
        self.verticalLayout.setObjectName("verticalLayout")
        self.runButton = QtWidgets.QPushButton(Form)
        self.runButton.setObjectName("runButton")
        self.verticalLayout.addWidget(self.runButton)
        self.stopButton = QtWidgets.QPushButton(Form)
        self.stopButton.setObjectName("stopButton")
        self.verticalLayout.addWidget(self.stopButton)
        self.log = QtWidgets.QTextBrowser(Form)
        self.log.setObjectName("log")
        self.verticalLayout.addWidget(self.log)
        self.retranslateUi(Form)
        QtCore.QMetaObject.connectSlotsByName(Form)

    def retranslateUi(self, Form):
        _translate = QtCore.QCoreApplication.translate
        Form.setWindowTitle(_translate("Form", "Form"))
        self.runButton.setText(_translate("Form", "run"))
        self.stopButton.setText(_translate("Form", "stop"))

class MyWidget(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent)
        self.ui = Ui_Form()
        self.ui.setupUi(self)

    def logOutput(self, text):
        self.ui.log.insertPlainText(text)
        self.ui.log.moveCursor(QTextCursor.End)

    @QtCore.pyqtSlot()
    def on_runButton_clicked(self):
        self.logOutput("start running...\n")
        self.worker = worker()
        self.worker.logChange.connect(self.logOutput)
        self.worker.start()

    @QtCore.pyqtSlot()
    def on_stopButton_clicked(self):
        if self.worker:
            self.worker.stop()
            self.logOutput("stop running...\n")
            self.worker = None

if __name__ == "__main__":
    app = QApplication(sys.argv)
    widget = MyWidget()
    widget.show()
    sys.exit(app.exec_())

test_mpi.cc

#include "mpi.h"
#include <iostream>
#include <chrono>
#include <thread>

int main(int argc, char** argv) {
  using namespace std::chrono_literals;
  MPI_Init(NULL, NULL);

  int world_size;
  MPI_Comm_size(MPI_COMM_WORLD, &world_size);

  int world_rank;
  MPI_Comm_rank(MPI_COMM_WORLD, &world_rank);

  if (world_rank == 0) {
    for (int i = 0; i < 20; i++) {
      std::this_thread::sleep_for(1000ms);
      std::cout << "This output is from test mpi program: " << i << std::endl;
    }

    std::cout << "Finished!" << std::endl;
  }

  MPI_Finalize();
  return 0;
}

当我单击

stopButton

时，我的任务管理器中显示 mpi 进程仍在运行。

我知道我可以使用

taskkill /IM test_mpi.exe /F

杀死它，但是这个命令也会终止其他程序启动的test_mpi.exe。所以我的问题是如何清楚地杀死由 Qprocess 启动的 mpi 程序。