最近这似乎是一个非常流行的问题/问题，但我似乎找不到解决问题的办法。
我用 C# 创建了一个简单的 Windows 服务来发送电子邮件。该应用程序运行良好，除了它的内存使用。该应用程序的前端是基于网络的，服务通过在目录中创建的文本文件排队。读取文本文件后，该服务从 MS SQL 数据库收集时事通讯信息和电子邮件地址，并开始每 4 秒发送一封电子邮件。通过任务管理器观察服务运行时，您可以看到 CPU 使用率每 4 秒上升一次，但立即回落。另一方面，内存似乎不是每封电子邮件都增加了 50-75k，而是每 3-4 封电子邮件增加了 50-75k。这将继续增加，直到发送完所有电子邮件。我刚发出大约。 2100 封电子邮件，内存使用量高达 100MB。我注意到的另一件事是，在发送完所有电子邮件后，内存使用量将保持在这个总数，直到我重新启动服务。当服务空闲时，内存运行在 6500k 左右。有人对我如何在邮件完成后减少和处理内存使用有任何建议吗？我的代码如下。任何帮助将不胜感激..
namespace NewsMailer
{
public partial class NewsMailer : ServiceBase
{
private FileSystemWatcher dirWatcher;
private static string filePath = @"E:\Intranets\Internal\Newsletter\EmailQueue";
private static string attachPath = @"E:\Intranets\Internal\Newsletter\Attachments";
private string newsType = String.Empty;
private string newsSubject = String.Empty;
private string newsContent = String.Empty;
private string userName = String.Empty;
private string newsAttachment = "";
private int newsID = 0;
private int emailSent = 0;
private int emailError = 0;
public NewsMailer()
{
InitializeComponent();
}
protected override void OnStart(string[] args)
{
dirWatcher = new FileSystemWatcher();
dirWatcher.Path = filePath;
dirWatcher.Created += new FileSystemEventHandler(ReadText);
dirWatcher.EnableRaisingEvents = true;
}
protected override void OnStop()
{
dirWatcher.EnableRaisingEvents = false;
dirWatcher.Dispose();
}
private void ClearVar()
{
newsType = String.Empty;
newsSubject = String.Empty;
newsContent = String.Empty;
userName = String.Empty;
newsAttachment = "";
newsID = 0;
emailSent = 0;
emailError = 0;
}
private void ReadText(object sender, FileSystemEventArgs e)
{
ClearVar();
SetLimits();
string txtFile = filePath + @"\QueueEmail.txt";
StreamReader sr = new StreamReader(txtFile);
string txtLine = String.Empty;
try
{
while ((txtLine = sr.ReadLine()) != null)
{
string[] lineCpl = txtLine.Split('§');
newsType = lineCpl[0];
userName = lineCpl[1];
newsID = Convert.ToInt32(lineCpl[2]);
}
}
catch (IOException ex)
{
SendExByMail("ReadText() IO Error", ex);
}
catch (Exception ex)
{
SendExByMail("ReadText() General Error", ex);
}
finally
{
sr.Close();
sr.Dispose();
}
GetNews();
}
[DllImport("kernel32.dll")]
public static extern bool SetProcessWorkingSetSize(IntPtr proc, int min, int max);
private void SetLimits()
{
GC.Collect();
GC.WaitForPendingFinalizers();
if (Environment.OSVersion.Platform == PlatformID.Win32NT)
SetProcessWorkingSetSize(Process.GetCurrentProcess().Handle, -1, -1);
}
private void DeleteText()
{
try
{
File.Delete(filePath + @"\QueueEmail.txt");
}
catch (IOException ex)
{
SendExByMail("DeleteText() IO Error", ex);
}
catch (Exception ex)
{
SendExByMail("DeleteText() General Error", ex);
}
}
private void GetNews()
{
string connectionString = ConfigurationManager.ConnectionStrings["contacts"].ConnectionString;
SqlConnection conn = new SqlConnection(connectionString);
string sqlSELECT = "SELECT newsSubject, newsContents, username, attachment FROM newsArchive " +
"WHERE ID = " + newsID;
SqlCommand comm = new SqlCommand(sqlSELECT, conn);
try
{
conn.Open();
using (SqlDataReader reader = comm.ExecuteReader())
{
while (reader.Read())
{
newsSubject = reader[0].ToString();
newsContent = reader[1].ToString();
userName = reader[2].ToString();
newsAttachment = reader[3].ToString();
}
reader.Dispose();
}
}
catch (SqlException ex)
{
SendExByMail("GetNews() SQL Error", ex);
}
catch (Exception ex)
{
SendExByMail("GetNews() General Error", ex);
}
finally
{
comm.Dispose();
conn.Dispose();
}
DeleteText();
GetAddress();
}
private void GetAddress()
{
string connectionString = ConfigurationManager.ConnectionStrings["contacts"].ConnectionString;
SqlConnection conn = new SqlConnection(connectionString);
string sqlSELECT = String.Empty;
if (newsType == "custom")
sqlSELECT = "SELECT DISTINCT email FROM custom";
else
sqlSELECT = "SELECT DISTINCT email FROM contactsMain WHERE queued = 'True'";
SqlCommand comm = new SqlCommand(sqlSELECT, conn);
try
{
conn.Open();
using (SqlDataReader reader = comm.ExecuteReader())
{
while (reader.Read())
{
try
{
if (CheckEmail(reader[0].ToString()) == true)
{
SendNews(reader[0].ToString());
Thread.Sleep(4000);
emailSent++;
}
else
{
SendInvalid(reader[0].ToString());
emailError++;
}
}
catch (SmtpException ex)
{
SendExByMail("NewsLetter Smtp Error", reader[0].ToString(), ex);
emailError++;
}
catch (Exception ex)
{
SendExByMail("Send NewsLetter General Error", reader[0].ToString(), ex);
emailError++;
}
finally
{
UnqueueEmail(reader[0].ToString());
}
}
reader.Dispose();
}
}
catch (SqlException ex)
{
SendExByMail("GetAddress() SQL Error", ex);
}
catch (Exception ex)
{
SendExByMail("GetAddress() General Error", ex);
}
finally
{
comm.Dispose();
conn.Dispose();
}
SendConfirmation();
}
private bool CheckEmail(string emailAddy)
{
bool returnValue = false;
string regExpress = @"^[\w-]+(?:\.[\w-]+)*@(?:[\w-]+\.)+[a-zA-Z]{2,7}$";
Match verifyE = Regex.Match(emailAddy, regExpress);
if (verifyE.Success)
returnValue = true;
return returnValue;
}
private void SendNews(string emailAddy)
{
string today = DateTime.Today.ToString("MMMM d, yyyy");
using (MailMessage message = new MailMessage())
{
SmtpClient smtpClient = new SmtpClient();
MailAddress fromAddress = new MailAddress("");
message.From = fromAddress;
message.To.Add(emailAddy);
message.Subject = newsSubject;
if (newsAttachment != "")
{
Attachment wusaAttach = new Attachment(attachPath + newsAttachment);
message.Attachments.Add(wusaAttach);
}
message.IsBodyHtml = true;
#region Message Body
message.Body = "";
#endregion
smtpClient.DeliveryMethod = SmtpDeliveryMethod.Network;
smtpClient.Host = "";
smtpClient.Credentials = new System.Net.NetworkCredential("");
smtpClient.Send(message);
smtpClient.ServicePoint.CloseConnectionGroup(smtpClient.ServicePoint.ConnectionName);
}
}
private void UnqueueEmail(string emailAddy)
{
string connectionString = ConfigurationManager.ConnectionStrings["contacts"].ConnectionString;
SqlConnection conn = new SqlConnection(connectionString);
string sqlStatement = String.Empty;
if (newsType == "custom")
sqlStatement = "UPDATE custom SET queued = 'False' WHERE email LIKE '" + emailAddy + "'";
else
sqlStatement = "UPDATE contactsMain SET queued = 'False' WHERE email LIKE '" + emailAddy + "'";
SqlCommand comm = new SqlCommand(sqlStatement, conn);
try
{
conn.Open();
comm.ExecuteNonQuery();
}
catch (SqlException ex)
{
SendExByMail("UnqueueEmail() SQL Error", ex);
}
catch (Exception ex)
{
SendExByMail("UnqueueEmail() General Error", ex);
}
finally
{
comm.Dispose();
conn.Dispose();
}
}
private void SendConfirmation()
{
SmtpClient smtpClient = new SmtpClient();
using (MailMessage message = new MailMessage())
{
MailAddress fromAddress = new MailAddress("");
MailAddress toAddress = new MailAddress();
message.From = fromAddress;
message.To.Add(toAddress);
//message.CC.Add(ccAddress);
message.Subject = "Your Newsletter Mailing Has Completed";
message.IsBodyHtml = true;
message.Body = "Total Emails Sent: " + emailSent +
"<br />Total Email Errors: " + emailError +
"<br />Contact regarding email errors if any were found";
smtpClient.Host = "";
smtpClient.Credentials = new System.Net.NetworkCredential("");
smtpClient.Send(message);
smtpClient.ServicePoint.CloseConnectionGroup(smtpClient.ServicePoint.ConnectionName);
}
ClearVar();
System.GC.Collect();
}
private void SendInvalid(string emailAddy)
{
SmtpClient smtpClient = new SmtpClient();
using (MailMessage message = new MailMessage())
{
MailAddress fromAddress = new MailAddress("");
MailAddress toAddress = new MailAddress("");
message.From = fromAddress;
message.To.Add(toAddress);
//message.CC.Add(ccAddress);
message.Subject = "Invalid Email Address";
message.IsBodyHtml = true;
message.Body = "An invalid email address has been found, please check the following " +
"email address:<br />" + emailAddy;
smtpClient.Host = "";
smtpClient.Credentials = new System.Net.NetworkCredential("");
smtpClient.Send(message);
smtpClient.ServicePoint.CloseConnectionGroup(smtpClient.ServicePoint.ConnectionName);
}
}
private void SendExByMail(string subject, Exception ex)
{
SmtpClient smtpClient = new SmtpClient();
using (MailMessage message = new MailMessage())
{
MailAddress fromAddress = new MailAddress("");
MailAddress toAddress = new MailAddress("");
message.From = fromAddress;
message.To.Add(toAddress);
//message.CC.Add(ccAddress);
message.Subject = subject;
message.IsBodyHtml = true;
message.Body = "An Error Has Occurred: <br />Exception: <br />" + ex.ToString();
smtpClient.Host = "";
smtpClient.Credentials = new System.Net.NetworkCredential("");
smtpClient.Send(message);
smtpClient.ServicePoint.CloseConnectionGroup(smtpClient.ServicePoint.ConnectionName);
}
}
private void SendExByMail(string subject, string body, Exception ex)
{
SmtpClient smtpClient = new SmtpClient();
using (MailMessage message = new MailMessage())
{
MailAddress fromAddress = new MailAddress("", "MailerService");
MailAddress toAddress = new MailAddress("");
message.From = fromAddress;
message.To.Add(toAddress);
//message.CC.Add(ccAddress);
message.Subject = subject;
message.IsBodyHtml = true;
message.Body = "An Error Has Occurred:<br /><br />" + body + "<br /><br />Exception: <br />" + ex.ToString();
smtpClient.Host = "";
smtpClient.Credentials = new System.Net.NetworkCredential("");
smtpClient.Send(message);
smtpClient.ServicePoint.CloseConnectionGroup(smtpClient.ServicePoint.ConnectionName);
}
}
}
}
最佳答案
System.Net.Mail.Attachment 实现了 IDisposable，所以我会在其上调用 Dispose()(使用 using ()) 更新:在 Reflector 中打开 MailMessage.Dispose() 会在任何附件上调用 Dispose。
此外，调用 GC.Collect() 实际上会导致大对象堆出现碎片。让框架负责垃圾收集。
你试过下载MemProfiler吗？ ？ (他们有试用版。通常在使用几分钟内就能收回成本!)
关于c# - 用于发送电子邮件的 C# Windows 服务中的内存泄漏，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/2140411/