我在C＃中有一个多线程程序。它读取文件列表。读取相关文件后，线程完成其任务并完成。我有一个线程数组，因为我有内存限制。当前线程终止后，我开始在同一线程中读取文件。我的问题是：尽管我使用互斥锁，但输入了线程并增加了文件计数器，并且读取了10个以上的文件（例如，在代码中）。我不知道为什么...
我尝试使用锁或监视器而不是互斥锁，但这不能解决问题。
我在代码后添加了打印输出。
readonly Mutex m1 = new Mutex();
int thIdx = 0, thAll = 0;
List<string> file_l = new List<string>();
Thread[,] arr = new Thread[4, 2];
static void Main()
{
for (int i = 0; i < cDev; i++)
{
for (int j = 0; j < cTrd; j++)
{
int xi = i, xj = j;
StartThread(xi, xj);
}
}
}
private void StartThread(int i, int j)
{
arr[i, j] = new Thread(() => Busy(i, j));
arr[i, j].Start();
Console.WriteLine($"started T[{i},{j}] StartTime = {DateTime.Now}.{DateTime.Now.Ticks}");
thIdx++;
thAll++;
}
private void CriticalSection(Mutex m, DelegateType fun)
{
m.WaitOne();
try
{
/* critical code */
fun();
}
finally
{
m.ReleaseMutex();
}
}
bool doneAll = false;
private void Busy(int i, int j)
{
// get file index for executind
int k = 0;
int k1 = 0;
// ** here is mutex and problem **
CriticalSection(m1, () =>
{
k = db.GetFileID(); // do id++ in db
k1 = k + 1;
if (k1 == 10) //file_l.Count
{
doneAll = true;
}
});
// Busy
Console.WriteLine($"busy T[{i},{j}] {k} - {file_l[k]}{i}{j}");
DateTime startTime = DateTime.Now;
string exec = "";
Thread.Sleep(3000);
Console.WriteLine($"finished T[{i},{j}] * {k} - ({DateTime.Now - startTime}) - command = {exec}");
thIdx--;
if (doneAll && thIdx == 0)
{
Console.WriteLine($"finished all - ({DateTime.Now - startTimeAll}) - files = {thAll}");
Console.WriteLine("end");
}
if (doneAll)
{
arr[i, j].Abort(); // release thread
}
else if (k1 < 10)
{
StartThread(i, j);
}
}
输出：
started T[0,0] StartTime = 28/08/2019 13:02:19.637025941396299385
started T[0,1] StartTime = 28/08/2019 13:02:19.637025941396339280
busy T[0,0] 0 - 3562634_04018610_2_CROP.MPG00
busy T[0,1] 1 - 6236814_04073221_1_CROP.MPG01
started T[3,0] StartTime = 28/08/2019 13:02:19.637025941396359231
busy T[3,0] 2 - 5886591_04081109_2_CROP.MPG30
started T[3,1] StartTime = 28/08/2019 13:02:19.637025941396379179
busy T[3,1] 3 - 3747967_04040496_3_CROP.MPG31
finished T[0,0] * 0 - (00:00:03.0278023) - command = sleep 3
finished T[3,0] * 2 - (00:00:03.0258075) - command = sleep 3
finished T[3,1] * 3 - (00:00:03.0238131) - command = sleep 3
started T[0,0] StartTime = 28/08/2019 13:02:22.637025941426637254
finished T[0,1] * 1 - (00:00:03.0278023) - command = sleep 3
started T[3,0] StartTime = 28/08/2019 13:02:22.637025941426647250
busy T[0,0] 4 - 3562909_04015124_3_CROP.MPG00
started T[3,1] StartTime = 28/08/2019 13:02:22.637025941426687119
busy T[3,1] 5 - 6347131_04081352_1_CROP.MPG31
busy T[3,0] 6 - 4005567_04043606_4_CROP.MPG30
started T[0,1] StartTime = 28/08/2019 13:02:22.637025941426766913
busy T[0,1] 7 - 4005566_04043601_2_CROP.MPG01
finished T[0,0] * 4 - (00:00:03.0055051) - command = sleep 3
started T[0,0] StartTime = 28/08/2019 13:02:25.637025941456762049
busy T[0,0] 8 - 3562434_04040432_2_CROP.MPG00
finished T[3,1] * 5 - (00:00:03.0324275) - command = sleep 3
finished T[3,0] * 6 - (00:00:03.0284380) - command = sleep 3
started T[3,1] StartTime = 28/08/2019 13:02:25.637025941457051293
finished T[0,1] * 7 - (00:00:03.0264398) - command = sleep 3
started T[3,0] StartTime = 28/08/2019 13:02:25.637025941457081178
busy T[3,0] 9 - 3740413_04012542_2_CROP.MPG30
started T[0,1] StartTime = 28/08/2019 13:02:25.637025941457160961
busy T[0,1] 10 - 3562404_04015032_2_CROP.MPG01
busy T[3,1] 11 - 5914063_04081061_1_CROP.MPG31
finished T[0,0] * 8 - (00:00:03.0058500) - command = sleep 3
finished T[3,0] * 9 - (00:00:03.0108370) - command = sleep 3
finished T[0,1] * 10 - (00:00:03.0310286) - command = sleep 3
finished T[3,1] * 11 - (00:00:03.0529614) - command = sleep 3
finished all - (00:00:09.1713083) - files = 12
end
我希望在这种情况下可以readind 10个文件，但在12个文件后它会停止
答案 0 :(得分：0)
我认为您的问题出在db.GetFileID（）函数中。您期望db中的值已更新，但实际上并没有。尝试使用全局变量（而不是此函数的结果）来控制线程数。