同一服务器上的WCF服务之间响应缓慢

我的UAT环境遇到了一个非常奇怪的问题。我有两个相互通信的WCF服务。在高层次上，我的web应用程序与业务层通信，并从那里将wcf请求传递到事务层，事务层处理所有请求并返回响应。我面临的问题是，事务层接收业务层发送的请求大约需要1分钟。有WCF服务部署在同一台服务器上，这个应用程序设置在生产中运行完美，所以我不确定发生了什么…

:

Web-frontend向业务层发送一个wcf请求以获取所有广告的列表。业务层执行一些安全检查(我已经从示例中删除了这些检查)，然后通过另一个WCF请求将请求传递到事务层。但是事务层需要1分钟才能接收到这个请求。业务层:

    public partial class AdsManagementService : IAdsManagementService
{
    public ListAdvertisementResponse ListAdvertisement(ListAdvertisementRequest request)
    {
        LogManager.Write("Initiated AdsManagement.AdsManagentService.ListAdvertisement()", LogCategory.Trace.ToString());
        var response = new ListAdvertisementResponse();
        response.Advertisements = new List<Advertisement>();
        LogManager.Write("Authentication token validated in AdsManagement.AdsManagentService.ListAdvertisement()", LogCategory.Event.ToString());
        var client = new AdService.AdsManagementServiceClient();
        try
        {
            response = client.ListAdvertisement(request);
            LogManager.Write("response received by AdsManagement.AdsManagentService.ListAdvertisement()", LogCategory.Event.ToString());
        }
        finally
        {
            try
            {
                client.Close();
            }
            catch (Exception ex)
            {
                LogManager.ExceptionHandler(ex);
            }
        }
    }
}

事务层

我在每个方法调用的开始/结束处添加了日志跟踪(BEGIN,END)，以显示处理该方法所需的时间。

 public ListAdvertisementResponse ListAdvertisement(ListAdvertisementRequest request)
    {
        LogManager.Write("BEGIN - ListAdvertisement", LogCategory.Event);
        var response = new ListAdvertisementResponse();
        try
        {                
            response.Advertisements = new List<AdvertisementType>();
            var ads = AdvertisementDataContextInstance.Advertisements;
            foreach (var ad in ads)
            {
                AdvertisementType advertisement = ConvertToAdvertisementType(ad);
                string filePath = AdFilePath + @"'" + ad.Code;
                if (Directory.Exists(filePath))
                {
                    string[] files = Directory.GetFiles(filePath);
                    foreach (string file in files)
                    {
                        advertisement.Files.Add(file);
                    }
                }
                response.Advertisements.Add(advertisement);
            }
        }
        catch (Exception ex)
        {
            response.ErrorAction = ResponseActionEnum.GeneralException;
            response.ErrorDetails = ex.Message;
            response.ErrorMessage = "Unable to list advertisements.";
        }
        LogManager.Write("END - ListAdvertisement", LogCategory.Event);
        return response;
    }

业务层日志跟踪

**Timestamp: 2/04/2013 9:23:08 AM**
Thread Name: 
Category: Trace
Severity: Information
Message: Initiated AdsManagement.AdsManagentService.ListAdvertisement()
**Timestamp: 2/04/2013 9:23:08 AM**
Thread Name: 
Category: Event
Severity: Information
Message: Authentication token validated in AdsManagement.AdsManagentService.ListAdvertisement()

**Timestamp: 2/04/2013 9:24:02 AM**
Thread Name: 
Category: Event
Severity: Information
Message: Response received by AdsManagement.AdsManagentService.ListAdvertisement()
**Timestamp: 2/04/2013 9:24:02 AM**
Thread Name: 
Category: Trace
Severity: Information
Message: Completed AdsManagement.AdsManagentService.ListAdvertisement()
**TRANSACTION LAYER LOG TRACE**
**2/04/2013 9:24:02 AM** - BEGIN - ListAdvertisement
**2/04/2013 9:24:02 AM** - BEGIN - ConvertToAdvertisementType
2/04/2013 9:24:02 AM - END - ConvertToAdvertisementType
2/04/2013 9:24:02 AM - BEGIN - ConvertToAdvertisementType
2/04/2013 9:24:02 AM - END - ConvertToAdvertisementType
2/04/2013 9:24:02 AM - BEGIN - ConvertToAdvertisementType
2/04/2013 9:24:02 AM - END - ConvertToAdvertisementType
**2/04/2013 9:24:02 AM** - END - ListAdvertisement

As you can see, there is roughly a 1 minute delay before the Transaction layer receives the request. I have no idea what is causing this. I think it might be the logging system (Microsoft.Practices.EnterpriseLibrary.Logging). I've noticed that it creates a separate log file almost every time it receives a request, almost as if the original log file is being kept open which stops it from writing to that file. Perhaps there is a 1 minute timeout on the logging before it decides to create a new log file and write to that?
I have the following log files in the logging directory for today's date: Every time I send a new request to the Transaction Layer, there is a 1min delay and then it creates a new log file:
RTITraceGeneral.log          02/04/2013 9:20 AM
RTIEvent.log                 02/04/2013 9:20 AM
c9d64c18-80d9-4993-b167-2070190fce51RTITraceGeneral.log    02/04/2013 9:20 AM
a7acf427-a919-4fe4-9832-d186e9e28c0cRTIEvent.log           02/04/2013 9:24 AM
8e35dbdc-3c94-4e93-866a-3affcbf5f082RTITraceGeneral.log    02/04/2013 9:24 AM