none
Hyper-V Domain Controller with Dynamic Memory allocation

    Question

  • I am deploying new Active Directory Domain Controllers on Hyper-V. I have asked for the traditional amount of resources such as Processor, Disk, Network, and Memory. My hypervisor admin stated that it is recommended to give servers in Hyper-v dynamic memory allocation rather than static memory.

    I have some concerns I would like to get some clarification on: 

    1) It is best practice to have enough memory to hold the entire DIT as well as what is necessary for running the OS and other functions. Will Dynamic memory cause a performance concern? My DC's are heavily used for large, expensive queries and a large user base. Current DIT size is ~4 gb. 

    2) From a security perpective, is there a concern when a DC is using dynamic memory allocation where the DIT is fully loaded into memory and the RAM is potentially shared back and forth among other servers located on that Hyper-V host server? ESX does not appear to have a dynamic memory allocation like this.

    Thank you for replies in advance.

    Brian B.

    Sunday, April 9, 2017 9:15 PM

Answers

All replies

  • Maybe this one helps.

    http://www.altaro.com/hyper-v/hyper-v-dynamic-memory-explanation-and-recommendations-2/

     

     



    Regards, Dave Patrick ....
    Microsoft Certified Professional
    Microsoft MVP [Windows Server] Datacenter Management

    Disclaimer: This posting is provided "AS IS" with no warranties or guarantees, and confers no rights.

    Sunday, April 9, 2017 9:23 PM
  • Thanks Dave.

    If I understand the article, the memory will be increased as demand is placed on the memory manager and will not be released until the machine is turned off. So if I have a start memory of 2gb and a max of 6gb but my DIT is 4gb, then will the available memory be increased at boot when AD tries to load the entire DIT into memory?

    AD "Tries" to load all of the DIT into memory and if that service sees only 2gb at start will it demand the additional memory to fully load the DIT?

    Brian B.

    Sunday, April 9, 2017 9:40 PM
  • I think yes basically unless the host does not have enough memory to satisfy all guests.

     

     



    Regards, Dave Patrick ....
    Microsoft Certified Professional
    Microsoft MVP [Windows Server] Datacenter Management

    Disclaimer: This posting is provided "AS IS" with no warranties or guarantees, and confers no rights.

    Sunday, April 9, 2017 9:58 PM