防止多线程网站消耗太多资源

Question

我已经为客户端构建了一个批量电子邮件发送网站，该客户端需要在单个发送中发送80,000封电子邮件。它基本上为发送创建了一个新线程，以便控制权可以交还给用户界面（这样可以加载反馈页面），然后为每个公司创建一个新线程，以便将电子邮件发送给收件人。这些电子邮件都排队，使用此代码：

// Loop through the companies and send their mail to the specified recipients 
     // while creating a new thread for each company 
     // A new thread is started so that the feedback page can load 
     SendingThread = Task.Factory.StartNew(() => 
     { 
      // This is a thread safe for loop 
      Parallel.ForEach<CompanyEntity>(companies, company => 
      { 
        // Start a new thread for each company send 
        Task.Factory.StartNew(() => 
        { 
         // Get the recipients for this company 
         var companyRecipients = GetSubscribersForCompany(company.Id, recipients); 

         // Send the newsletter to the company recipients 
         var success = SendNewsletterForCompany(newsletter, company, companyRecipients, language, 
                   version, company.AdvertCollectionViaNewsletterCompanyAdvertLink, newsletter.NewsletterType, email); 

         // Add the status update so the front end can view a list of updated conpany statuses 
         if (success) 
          AddStatusUpdate(company.CompanyTitle + " has completed processing."); 

         // Starts sending the emails if the engine hasn't already been started 
         SendEngine.Start(CurrentSmtpClient, this); 

        }).ContinueWith(antecendent => EndCompaniesSendUpdate(companiesToProcess, companiesProcessed), TaskContinuationOptions.OnlyOnRanToCompletion); 
      }); 
     }, new CancellationToken(), TaskCreationOptions.LongRunning, TaskScheduler.Default); 

虽然电子邮件排队，发送引擎接管并从队列中拉电子邮件，然后使用新的Parallel类并将它们发送：

Action action =() => 
     { 
      MailMessage message; 
      while (queue.TryDequeue(out message)) 
      { 
       SendMessage(sendingServer, message, factory); 
      } 
     }; 

     // Start 5 concurrent actions to send the messages in parallel. 
     Parallel.Invoke(action, action, action, action, action); 

所有这些都很棒，可以在10分钟内发送40,000条新闻。唯一的问题是服务器上的RAM和CPU在这10分钟内100％被占用。这会影响服务器上的其他站点，因为它们无法访问。

有什么办法来限制IIS 7.5中发送应用程序的资源使用情况，或者通过更改上面的代码？

Answer 1

问题：

• 你生成一个并行的foreach中的一个线程，“平行”的一部分意味着它已经产卵的身体线程。您在并行调用中嵌套并行调用，而不是在另一个“调用”内部的并行ForEach内执行“调用”。

• 你正在一个线程内部运行一个while循环，没有CPU的休息。这是并行调用5x。

答案：

CPU使用率，你需要给你的处理喘息。在你的While TryDequeue循环中放上一个短暂的睡眠。

 MailMessage message; 
     while (queue.TryDequeue(out message)) 
     { 
      SendMessage(sendingServer, message, factory); 
      Thread.Sleep(16); 
     } 

对于RAM和CPU使用情况，您需要一次处理LESS。

 SendingThread = Task.Factory.StartNew(() => 
     { 
      foreach(var company in companies) 
      { 
         // Get the recipients for this company 
         var companyRecipients = GetSubscribersForCompany(company.Id, recipients); 

         // Send the newsletter to the company recipients 
         var success = SendNewsletterForCompany(newsletter, company, companyRecipients, language, 
                   version, company.AdvertCollectionViaNewsletterCompanyAdvertLink, newsletter.NewsletterType, email); 

         // Add the status update so the front end can view a list of updated conpany statuses 
         if (success) 
          AddStatusUpdate(company.CompanyTitle + " has completed processing."); 

         // Starts sending the emails if the engine hasn't already been started 
         SendEngine.Start(CurrentSmtpClient, this); 


      } 
     }, new CancellationToken(), TaskCreationOptions.LongRunning, TaskScheduler.Default);