Question

我在使用C＃编写的Windows服务中的内存管理方面遇到了一些问题（框架3.5，visual studio 2008）。

服务运行正常，使用Timer和CallBack每3分钟触发一次程序。因此，Windows任务管理器中的内存在每个计时器运行时都会缓慢增长。

您是否知道如何解决此问题？

为了简化问题，下面是一个非常简单的代码，可以解决同样的问题：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Linq;
using System.ServiceProcess;
using System.Text;
using System.Threading;
using System.IO;

namespace svcTest
{
public partial class svcTest : ServiceBase
{

    private Timer tmr;
    private TimerCallback tmrCallBack;

    public svcTest()
    {
        InitializeComponent();
    }

    protected override void OnStart(string[] args)
    {
        FileStream fs = new FileStream(@"c:\svclog.txt", FileMode.OpenOrCreate, FileAccess.Write);
        StreamWriter m_streamWriter = new StreamWriter(fs);
        m_streamWriter.BaseStream.Seek(0, SeekOrigin.End);
        m_streamWriter.WriteLine("Service Started on " + DateTime.Now.ToLongDateString() + " at " + DateTime.Now.ToLongTimeString());
        m_streamWriter.WriteLine(" *----------------*");
        m_streamWriter.Flush();
        m_streamWriter.Close();

        tmrCallBack = new TimerCallback(goEXE);
        tmr = new Timer(tmrCallBack, null, 0, 1000 * 60 * 1 / 2);
    }

    protected override void OnStop()
    {
        FileStream fs = new FileStream(@"c:\svclog.txt", FileMode.OpenOrCreate, FileAccess.Write);
        StreamWriter m_streamWriter = new StreamWriter(fs);
        m_streamWriter.BaseStream.Seek(0, SeekOrigin.End);
        m_streamWriter.WriteLine("Service Stopped on " + DateTime.Now.ToLongDateString() + " at " + DateTime.Now.ToLongTimeString());
        m_streamWriter.WriteLine(" *----------------*");
        m_streamWriter.Flush();
        m_streamWriter.Close();

        tmr.Dispose();
    }

    private void goEXE(Object state)
    {
        Console.WriteLine(DateTime.Now.ToString());

        FileStream fs = new FileStream(@"c:\svclog.txt", FileMode.OpenOrCreate, FileAccess.Write);
        StreamWriter m_streamWriter = new StreamWriter(fs);
        m_streamWriter.BaseStream.Seek(0, SeekOrigin.End);
        m_streamWriter.WriteLine("Service running on " + DateTime.Now.ToLongDateString() + " at " + DateTime.Now.ToLongTimeString());
        m_streamWriter.WriteLine(" *----------------*");
        m_streamWriter.Flush();
        m_streamWriter.Close();

    }

    }
}

任何帮助将不胜感激！

斯特凡诺

Answer 1

您没有处置FileStream。垃圾收集器可以为您调用Dispose()，但它是非确定性的（即您不知道何时/是否会发生）。这可能决定不要打扰。因此，建议的最佳做法是考虑在IDisposable语句中包装实现using的任何内容：

using (FileStream fs = new FileStream(@"c:\svclog.txt", FileMode.OpenOrCreate, FileAccess.Write)
{
    using (using (StreamWriter m_streamWriter = new StreamWriter(fs)))
    {
        m_streamWriter.BaseStream.Seek(0, SeekOrigin.End);
        m_streamWriter.WriteLine("Service Started on " + DateTime.Now.ToLongDateString() + " at " + DateTime.Now.ToLongTimeString());
        m_streamWriter.WriteLine(" *----------------*");
    }
}

出于维护和DRY原因，您还应该考虑将文件编写代码重构为单独的方法：

private void Log(string message)
{
    using (FileStream fs = new FileStream(@"c:\svclog.txt", FileMode.OpenOrCreate, FileAccess.Write)
    {
        using (using (StreamWriter m_streamWriter = new StreamWriter(fs)))
        {
            m_streamWriter.BaseStream.Seek(0, SeekOrigin.End);
            m_streamWriter.WriteLine(message + " " + DateTime.Now.ToLongDateString() + " at " + DateTime.Now.ToLongTimeString());
            m_streamWriter.WriteLine(" *----------------*");
        }
    }
}

protected override void OnStart(string[] args)
{
    Log("Service Started");

    tmrCallBack = new TimerCallback(goEXE);
    tmr = new Timer(tmrCallBack, null, 0, 1000 * 60 * 1 / 2);
}

protected override void OnStop()
{
    Log("Service Stopped");

    tmr.Dispose();
}

private void goEXE(Object state)
{
    Console.WriteLine(DateTime.Now.ToString());

    Log("Service running");
}

Answer 2

此外，.NET的垃圾收集在遇到某些最佳参数时运行。如果系统内存不足，可能会认为运行GC.Collect太昂贵了，因此你的非引用但仍然在内存中的对象会继续保持这种状态。

Answer 3

我会假设您的文件不断增长，因为您要添加新行到最后，因此，节水器消耗更多的内存。

我宁愿在programm启动时创建一个流编写器而不是在回调时这样做。但是你会锁定一个文件通过您的服务。

Answer 4

public class Logger : IDisposable
{
    public void Log(string message)
    {
        using (FileStream fs = new FileStream(@"c:\svclog.txt", FileMode.OpenOrCreate, FileAccess.Write)
        {
            using (using (StreamWriter m_streamWriter = new StreamWriter(fs)))
            {
                m_streamWriter.BaseStream.Seek(0, SeekOrigin.End);
                m_streamWriter.WriteLine(message + " " + DateTime.Now.ToLongDateString() + " at " + DateTime.Now.ToLongTimeString());
                m_streamWriter.WriteLine(" *----------------*");
            }
        }
    }
    public void Dispose()
    {
        GC.SuppressFinalize(this);

    }
}

Answer 5

最好使用File.AppendAllText(path, content);，它将处理所有内存泄漏。

c＃windows服务内存问题（内存泄漏？）

5 个答案: