5 Replies Latest reply on Jun 14, 2010 3:17 PM by mark_h_@intel

    Freezes in communication on Intel PRO/1000 PF Server Adapter

    roman921

      I have a networking issue, which I have problems in troubleshooting and I would appreciate any idea and feedback.

       

      We have a box dedicated for specific communication with remote server over dedicated fiber line. On our side we have Intel PRO/1000 PF Server Adapter with a gigabit link. Intel Driver Update utility shows latest drivers and the operating system is Windows 7 Pro x64.

       

      Product DetectedIntel(R) 82572EI based Network Controller(OEM)
      Current Driver Installed9.13.41.0
      Your driver is current.

       

      Bandwidth utilization and CPU load both are somewhere near 1% and never go much higher than this.

       

      The application continuously receives the data and here is the problem. From time to time, a few times hourly there would be a freeze for up to several seconds and after it, the application would receive a large block of data, as if the was a contention and then all the accumulated data is finally delivered.

       

      It is assumed that remote side delivers data in a good fashion without irregularities of the mentioned kind (other clients are not suffering from this issue), is there any way to troubleshoot the problem from our end?

       

      I noticed that adapter configuration includes Interrupt Moderation feature which seemed to be relevant and I tried to use low levels, or disable at all. This had no effect on the smoothness of received data.

       

      I would really appreciate any suggestions on the issue, thanks.

        • 1. Re: Freezes in communication on Intel PRO/1000 PF Server Adapter
          milespenner

          Hi roman921 -

          When you say "freeze up" do you mean the whole computer (i.e., mouse does not move, etc) or do you mean that the network activity drops to 0% and then jumps up to say 10% (just throwing out numbers here) and then will transition back to the normal 1% rate?

           

          Thank you for using Intel Ethernet.

          Cheers,

          -- miles

          • 2. Re: Freezes in communication on Intel PRO/1000 PF Server Adapter
            roman921

            Thank you for attention to my issue. Since the server is in data center and I acces it remotely, I unfortunately cannot clarify other freeze symptomps that may or may not take place there. I can only see the issue retroactively, and from software side it was isolated to TCP socket operation. The application is waiting for data from socket and while normally it receives data in small increments, at the issue time there is a delay and then a large buffers comes in.

             

            For example, time and number of bytes received:

             

            12:47:13.493    184

            12:47:13.495    280   

            12:47:13.497    274   

            12:47:13.497    179   

            12:47:13.503    319   

            12:47:13.514    274   

            12:47:13.518    185   

            12:47:13.518    259   

            12:47:13.519    185   

            12:47:13.519    180   

            12:47:13.519    185   

            12:47:13.527    184   

            12:47:13.529    264   

            12:47:13.532    179   

            /* Here comes a delay of 0.77 seconds */

            12:47:14.303    280   

            12:47:14.304    84713   

            12:47:14.306    272   

            12:47:14.306    272   

            12:47:14.321    179   

            ...

             

            This pattern repeats all the time: a delay, then a small "normal" buffer is received and next to it there is a large buffer, which may refer to several seconds of traffic.

            • 3. Re: Freezes in communication on Intel PRO/1000 PF Server Adapter
              milespenner

              Hi roman921 -

              That is definitely odd pattern you are seeing there.  I would recommend that a network sniff be taken for this connection and see if there is any packet loss or retransmission going on during this pause in the traffic.  There are a number possible causes including an intermediate switch dropping frames (this is normal for some switches through an algorithm called RED or other associated algorithms) to an issue with a card.

               

              @ MarkH - would you recommend any additional action for roman921?

              Cheers,

              -- miles

              • 4. Re: Freezes in communication on Intel PRO/1000 PF Server Adapter
                roman921

                Thanks, I will try to use sniffer to get some details. Apart from that, is there any chance that hard drive activity affects in some way networking, such as throttling. It was a pure guessing but I did have a suspicion that there is a correlation between peak disk activity and communication delays. Anyway, I am going to use sniffer to gather more information, thanks for your help.

                • 5. Re: Freezes in communication on Intel PRO/1000 PF Server Adapter
                  mark_h_@intel

                  If the data being transferred is being written to a hard drive then that could be your bottleneck. If you run short on physical RAM and end up with pages being swapped between RAM and the hard driver, the bottleneck could be made worse.

                   

                  Once you look at the Ethernet trace, you might have a better idea about whether the network connection itself seems to be working properly.