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Should TCP offloading be disabled on S4B servers? RRS feed

  • Question

  • Hello,

    What is the recommendation for S4B virtual servers regarding TCP offloading on network interfaces? I found articles recommending to disable it in most cases but I cannot find an answer specific to S4B servers.

    Regards,

    Francois

    Monday, October 24, 2016 2:54 PM

Answers

  • for Lync in VM please find microsoft recommendation for network

    Use Virtual Machine Queue (VMQ)
    Use to optimize synthetic NIC performance
    Use physical NIC segregation for host versus guest communications
    VM Chimney (TCP offload) should be disabled
    To minimize NIC performance impacts by offloading TCP processing
    Single Root I/O Virtualization (SR-IOV) is recommended
    The specific configuration depends on the host chipset and network driver/adaptor

    for reference: video.ch9.ms/sessions/lync/2014/SERV305_%20Gunn.pptx 

     
    • Proposed as answer by GUIz49 Monday, October 24, 2016 9:55 PM
    • Marked as answer by FrancoisCA Tuesday, October 25, 2016 6:43 AM
    Monday, October 24, 2016 9:55 PM

All replies

  • Hi Francois,

    I don't think TCP offload will make more performance improvement for FE servers. 

    Based on my understanding,

    The FE servers does not transfer large data packets as SQL or File servers. Hence offloading will not make any differences in the FE performances. 

    But for the SQL(backend servers), if there is a replication then this would help.

    When to use TCP Chimney Offload

    Because of the overhead associated with moving TCP/IP processing to the network adapter, TCP Chimney Offload offers the most benefit to applications that have long-lived connections and transfer large amounts of data. Servers that perform database replication, function as file servers, or perform backup functions are examples of computers that may benefit when you enable TCP Chimney Offload.

    To determine if TCP Chimney Offload will benefit an application, run the application with TCP Chimney Offload or Virtual Machine Chimney disabled to establish a performance baseline. While the application is running, capture CPU utilization for each CPU and the network throughput. After you establish the baseline, set the operating system mode of TCP Chimney Offload to either automatic or enabled, as appropriate, and then compare the CPU utilizations and network throughput.


    - Muralidharan. Please mark as answer/useful if my contribution helps you.

    Monday, October 24, 2016 4:57 PM
  • for Lync in VM please find microsoft recommendation for network

    Use Virtual Machine Queue (VMQ)
    Use to optimize synthetic NIC performance
    Use physical NIC segregation for host versus guest communications
    VM Chimney (TCP offload) should be disabled
    To minimize NIC performance impacts by offloading TCP processing
    Single Root I/O Virtualization (SR-IOV) is recommended
    The specific configuration depends on the host chipset and network driver/adaptor

    for reference: video.ch9.ms/sessions/lync/2014/SERV305_%20Gunn.pptx 

     
    • Proposed as answer by GUIz49 Monday, October 24, 2016 9:55 PM
    • Marked as answer by FrancoisCA Tuesday, October 25, 2016 6:43 AM
    Monday, October 24, 2016 9:55 PM