none
Large file download issues - IIS 7

    Question

  • Any direction to solution of my problem will be appreciated.

    I have an .net 2.0 application hosted on Windows 2008 standard Server which runs on VMWare. The Server has Intel Xeon CPU E7540 @2.00 GHz and 4 GB of RAM. The version of IIS is 7.0. My application consists of a website which hosts files to be downloaded and a windows application installed on client pc. There is a .net webservice as well which is accessed by Windows applications installed on client PCs of our customers which authenticates and transports files from the server to client PC using https protocol.

    The problem is whenever any user is trying to download a file using the windows client, I see high CPU spikes in the task manager. CPU hits 100% and IIS worker process (w3wp.exe) gets suspended. It will automatically restart sometimes but not always. Sometime the worker process will not start and file transfer fails to work.

    Relatively smaller files get transported but for large files (sizing more than 2 GB), download fails. This functionality worked well on our old server which had the following configuration:

    OS - Windows 2003 Standard 32 bit, 8GB of RAM on a physical server (note- this was not a VMWare system).

    I am having hard time get a proper resolution for this issue. Any help will be greatly appreciated.

    Thank you,

    Rahul Rakesh


    Rahul Rakesh

    Tuesday, December 04, 2012 12:21 PM

Answers

  • As far as I can see, there's no reported compatibility issues between running a virtual server on vmware that's using IIS 7.0, however if that's the only thing that's changed, I'd assume that'd be the problem. I'd suggest getting together some IIS logs and posting them here, so that we can pinpoint what's going on here.

    The logs are located in the inetpub\logs directory. Please recreate the issue, then post a snippet of the log pertaining to the period in time when the problem occured, or post the log onto SkyDrive or your preferred sharing environment.


    -Junior

    • Marked as answer by Rakesh Rahul Wednesday, December 05, 2012 7:16 AM
    Tuesday, December 04, 2012 8:27 PM

All replies

  • As far as I can see, there's no reported compatibility issues between running a virtual server on vmware that's using IIS 7.0, however if that's the only thing that's changed, I'd assume that'd be the problem. I'd suggest getting together some IIS logs and posting them here, so that we can pinpoint what's going on here.

    The logs are located in the inetpub\logs directory. Please recreate the issue, then post a snippet of the log pertaining to the period in time when the problem occured, or post the log onto SkyDrive or your preferred sharing environment.


    -Junior

    • Marked as answer by Rakesh Rahul Wednesday, December 05, 2012 7:16 AM
    Tuesday, December 04, 2012 8:27 PM
  • Thanks for your reply, Junior.

    There is one more change to the server. We have upgraded our database from SQL Server 2005 express to SQL Server 2008 Standard R2.

    In order to resolve this issue I did a CPU upgrade from single CPU to 2 CPUs. Adding CPUs didn't help. We will not be able to increase physical memory to more than 4GB because of VM Constraints. VM experts have denied increasing the physical memory because they think that adding resources into VM environment can actually have a detrimental effect within the VMware environment as it spends more time waiting for its allocation of resources, as they are shared.

    I have only 1 w3wp.exe running on the server. The available physical and kernel memory at the time problem occurs is (as seen in Task Manager):

    physical mem(MB)
    Total- 4094
    Cached-1560
    Free-292

    Kernel Mem (MB)
    Total-132
    Paged-103
    NonPaged-160

    P.S.: I see that memory (private working set) for IIS worker process is around 125800 K and for SQL Server 2008 it is 409136 K.

    Please find the logs from the server below. Also find the log uploaded to microsoft skydrive at:

    <iframe src="https://skydrive.live.com/embed?cid=F7D9B85F60B8810C&resid=F7D9B85F60B8810C%21123&authkey=AAmxmxuG1g80uQc" width="98" height="120" frameborder="0" scrolling="no"></iframe>

    File Name: u_ex121204.log

    ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

    2012-12-04 10:08:24 192.127.46.171 GET /download.ashx ContentID=541&getfilename=true&guid=b10fb5cf-0d6f-4744-8a86-744a0de15c63 80 - 153.58.47.150 - 200 0 64 925
    2012-12-04 10:09:17 192.127.46.171 GET /download.ashx ContentID=541&guid=b10fb5cf-0d6f-4744-8a86-744a0de15c63 80 - 153.58.47.150 - 200 0 64 52554
    2012-12-04 10:10:57 192.127.46.171 GET /download.ashx ContentID=541&guid=b10fb5cf-0d6f-4744-8a86-744a0de15c63 80 - 153.58.47.150 - 200 0 64 56924
    #Software: Microsoft Internet Information Services 7.0
    #Version: 1.0
    #Date: 2012-12-04 10:15:39
    #Fields: date time s-ip cs-method cs-uri-stem cs-uri-query s-port cs-username c-ip cs(User-Agent) sc-status sc-substatus sc-win32-status time-taken
    2012-12-04 10:15:39 192.127.46.171 GET / - 80 1 153.58.47.150 Mozilla/4.0+(compatible;+MSIE+7.0;+Windows+NT+5.1;+Trident/4.0;+.NET+CLR+3.0.4506.2152;+.NET+CLR+3.5.30729;+.NET+CLR+2.0.50727;+.NET4.0C;+.NET4.0E) 302 0 0 11041
    2012-12-04 10:17:00 192.127.46.171 GET /download.ashx ContentID=541&guid=b10fb5cf-0d6f-4744-8a86-744a0de15c63 80 - 153.58.47.150 - 200 0 64 98510
    2012-12-04 10:18:18 192.127.46.171 GET /download.ashx ContentID=541&guid=b10fb5cf-0d6f-4744-8a86-744a0de15c63 80 - 153.58.47.150 - 200 0 64 64180
    2012-12-04 10:19:58 192.127.46.171 GET /download.ashx ContentID=541&guid=b10fb5cf-0d6f-4744-8a86-744a0de15c63 80 - 153.58.47.150 - 200 0 64 61673
    2012-12-04 10:21:12 192.127.46.171 GET /download.ashx ContentID=541&guid=b10fb5cf-0d6f-4744-8a86-744a0de15c63 80 - 153.58.47.150 - 200 0 64 64530
    2012-12-04 10:23:35 192.127.46.171 GET /download.ashx ContentID=541&guid=b10fb5cf-0d6f-4744-8a86-744a0de15c63 80 - 153.58.47.150 - 200 0 64 89329
    #Software: Microsoft Internet Information Services 7.0
    #Version: 1.0
    #Date: 2012-12-04 10:46:04
    #Fields: date time s-ip cs-method cs-uri-stem cs-uri-query s-port cs-username c-ip cs(User-Agent) sc-status sc-substatus sc-win32-status time-taken
    2012-12-04 10:46:04 192.127.46.171 GET /download.ashx ContentID=541&guid=b10fb5cf-0d6f-4744-8a86-744a0de15c63 80 - 153.58.47.150 - 200 0 995 1320820
    #Software: Microsoft Internet Information Services 7.0
    #Version: 1.0
    #Date: 2012-12-04 11:25:46
    #Fields: date time s-ip cs-method cs-uri-stem cs-uri-query s-port cs-username c-ip cs(User-Agent) sc-status sc-substatus sc-win32-status time-taken
    2012-12-04 11:25:46 192.127.46.171 GET /download.ashx ContentID=541&guid=b10fb5cf-0d6f-4744-8a86-744a0de15c63 80 - 153.58.47.150 - 200 0 0 2325465

    ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

    Please let me know if you see there is any problem. Thank you for your time, Junior.

    Regards,

    Rahul Rakesh


    Rahul Rakesh

    Wednesday, December 05, 2012 7:16 AM
  • Also, The log file C:\WINDOWS\system32\LogFiles\HTTPERR\httperr1.log file looks like this when the problem occurred.

    #Software: Microsoft HTTP API 2.0
    #Version: 1.0
    #Date: 2012-12-04 10:46:04
    #Fields: date time c-ip c-port s-ip s-port cs-version cs-method cs-uri sc-status s-siteid s-reason s-queuename
    2012-12-04 10:46:04 153.58.47.150 4192 192.127.46.171 80 HTTP/1.1 GET /download.ashx?ContentID=541&guid=b10fb5cf-0d6f-4744-8a86-744a0de15c63 - 4 Connection_Abandoned_By_ReqQueue DefaultAppPool
    2012-12-04 11:27:58 153.58.47.150 4304 192.127.46.171 80 - - - - - Timer_ConnectionIdle -
    2012-12-05 07:05:52 153.58.47.188 1569 192.127.46.171 80 - - - - - Timer_ConnectionIdle -
    2012-12-05 07:05:52 153.58.47.188 1570 192.127.46.171 80 - - - - - Timer_ConnectionIdle -


    Rahul Rakesh

    Wednesday, December 05, 2012 10:16 AM