asp.net - 防止多线程网站消耗过多资源

Question

我为客户建立了一个批量电子邮件发送网站，需要一次发送 80,000 封电子邮件。它基本上为发送创建一个新线程，以便可以将控制权交还给 UI(以便可以加载反馈页面)，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。所有电子邮件均使用以下代码排队:

// 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);

当电子邮件排队时，发送引擎接管并从队列中提取电子邮件，然后使用新的 Parallel 类发送它们:

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);

所有这些都非常有效，可以在大约 10 分钟内发送 40,000 份新闻通讯。唯一的问题是服务器上的 RAM 和 CPU 在这 10 分钟内被 100% 消耗。这会影响服务器上的其他站点，因为它们无法访问。

有没有办法在 IIS 7.5 中或通过更改上面的代码来限制发送应用程序的资源使用？

Answer 1

问题:

• 您正在 Parallel ForEach 内部生成一个线程，“Parallel”部分意味着它已经为主体生成了一个线程。您正在将 Parallel Invoke 而不是 Action 嵌套在另一个 Action 的 Parallel ForEach 中。

• 您正在线程内运行 while 循环，CPU 没有休息。这就是并行调用 5 次。

答案:

对于 CPU 使用情况，您需要让处理休息一下。在您的 While TryDequeue 循环中放置一个短暂的 sleep 。

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

对于 RAM 和 CPU 使用情况，您需要立即处理 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);