c# - 后台 worker 有限制吗？技术常识

Question

在Program.cs中，我具有以下检查方法以及将5个SQL数据库与中央服务器同步的方法。每个程序都是彼此独立的，因此我想通过使它们全部同时运行来加快程序的加载时间。

不幸的是，这一次工作非常不稳定，然后又不是。本地数据库是SQLExpress 2005，中央数据库是SQL Server Standard 2005。

这些连接可以有多少个连接是否有限制？后台 worker 呢，我一次只能运行这么多吗？我敢肯定，这样做有一种更为 Eloquent 方法，我很想听听(见)他们。

这就是我在Program.cs的Main()中如何称呼它->
if(IsSqlAvailable())
SyncNow();

internal static void SyncNow()
    {



            #region ConnectDB Merge Sync Background Thread

            BackgroundWorker connectBW = new BackgroundWorker
                                             {
                                                 WorkerReportsProgress = false,
                                                 WorkerSupportsCancellation = true
                                             };
            connectBW.DoWork += new DoWorkEventHandler(connectBW_DoWork);
            if (connectBW.IsBusy != true)
                connectBW.RunWorkerAsync();

            #endregion

            #region aspnetDB Merge Sync Background Thread

            BackgroundWorker aspBW = new BackgroundWorker
                                         {
                                             WorkerReportsProgress = false,
                                             WorkerSupportsCancellation = true
                                         };
            aspBW.DoWork += new DoWorkEventHandler(aspBW_DoWork);
            if (aspBW.IsBusy != true)
                aspBW.RunWorkerAsync();

            #endregion

            #region MatrixDB Merge Sync Background Thread

            BackgroundWorker matrixBW = new BackgroundWorker
                                            {
                                                WorkerReportsProgress = false,
                                                WorkerSupportsCancellation = true
                                            };
            matrixBW.DoWork += new DoWorkEventHandler(matrixBW_DoWork);
            if (matrixBW.IsBusy != true)
                matrixBW.RunWorkerAsync();

            #endregion



            #region CMODB Merge Sync Background Thread

            BackgroundWorker cmoBW = new BackgroundWorker
                                         {
                                             WorkerReportsProgress = false,
                                             WorkerSupportsCancellation = true
                                         };
            cmoBW.DoWork += new DoWorkEventHandler(cmoBW_DoWork);
            if (cmoBW.IsBusy != true)
                cmoBW.RunWorkerAsync();

            #endregion

            #region MemberCenteredPlanDB Merge Sync Background Thread

            BackgroundWorker mcpBW = new BackgroundWorker
                                         {
                                             WorkerReportsProgress = false,
                                             WorkerSupportsCancellation = true
                                         };
            mcpBW.DoWork += new DoWorkEventHandler(mcpBW_DoWork);
            if (mcpBW.IsBusy != true)
                mcpBW.RunWorkerAsync();

            #endregion

    }

    static void mcpBW_DoWork(object sender, DoWorkEventArgs e)
    {
        BackgroundWorker worker = sender as BackgroundWorker;
        try
        {
            MergeRepl mcpMergeRepl = new MergeRepl(SystemInformation.ComputerName + "\\SQLEXPRESS", "WWCSTAGE", "MemberCenteredPlan", "MemberCenteredPlan", "MemberCenteredPlan");
            mcpMergeRepl.RunDataSync();
            areAllInSync += 1; 
        }
        catch (Exception)
        {
            if (worker != null) worker.CancelAsync();
        }
    }

    static void cmoBW_DoWork(object sender, DoWorkEventArgs e)
    {
        BackgroundWorker worker = sender as BackgroundWorker;
        try
        {
            MergeRepl cmoMergeRepl = new MergeRepl(SystemInformation.ComputerName + "\\SQLEXPRESS", "WWCSTAGE", "CMO", "CMO", "CMO");
            cmoMergeRepl.RunDataSync();
            areAllInSync += 1; 
        }
        catch (Exception)
        {
            if (worker != null) worker.CancelAsync();
        }
    }

    static void connectBW_DoWork(object sender, DoWorkEventArgs e)
    {
        BackgroundWorker worker = sender as BackgroundWorker;
        try
        {
            MergeRepl connectMergeRepl = new MergeRepl(SystemInformation.ComputerName + "\\SQLEXPRESS", "WWCSTAGE", "CONNECT", "Connect", "Connect");
            connectMergeRepl.RunDataSync();
            areAllInSync += 1; 
        }
        catch (Exception)
        {
            if (worker != null) worker.CancelAsync();
        }
    }

    static void matrixBW_DoWork(object sender, DoWorkEventArgs e)
    {
        BackgroundWorker worker = sender as BackgroundWorker;
        try
        {
            MergeRepl matrixMergeRepl = new MergeRepl(SystemInformation.ComputerName + "\\SQLEXPRESS", "WWCSTAGE", "MATRIX", "MATRIX", "MATRIX");
            matrixMergeRepl.RunDataSync();
            areAllInSync += 1; 
        }
        catch (Exception)
        {
            if (worker != null) worker.CancelAsync();
        }
    }

    static void aspBW_DoWork(object sender, DoWorkEventArgs e)
    {
        BackgroundWorker worker = sender as BackgroundWorker;
        try
        {
            MergeRepl aspnetdbMergeRepl = new MergeRepl(SystemInformation.ComputerName + "\\SQLEXPRESS", "WWCSTAGE", "aspnetdb", "aspnetdb", "aspnetdb");
            aspnetdbMergeRepl.RunDataSync();
            areAllInSync += 1; 
        }
        catch (Exception)
        {
            if (worker != null) worker.CancelAsync();
        }

    }

Answer 1

您需要更具体地说明“易碎性”是什么，它如何体现。如果我正确理解这一点，则说明您在缺少代理支持的情况下尝试手动驱动具有RMO类的合并复制。

需要注意的一件事是，SQL Express仅支持一个调度程序，因此向其中添加多个工作程序(待处理的请求)不会有太大的区别，它们只会堆积在可运行的队列中并争夺一个CPU来运行它们。

其次，我不确定RMO复制类(我假设您使用的类)是否支持在多个并行实例中进行同步，因此，我可能没有必要在每个db上仅做一个BackgroundWorker了(我对此可能是错误的)一个，无论如何我都不是RMO专家)。