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Mudassar's avatar
Mudassar
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Aug 24, 2021

Adding and removing resources from vCMP.

I want to remove cores from a vCMP and assign it to another one. Will removing cores from a vCMP impact it? Same for adding operation as well.

  • Hi Mudassar,

     

    Easy part first - adding resources will very likely NOT have a negative impact. The worst thing I can see happening is having some strange behavior on traffic distribution and persistance due to CMP (https://support.f5.com/csp/article/K14358). This can be more evident if the amount of traffic is relatively low.

     

    Now, if you remove resources, I'm going to say it depends. Less resources mean less capacity to process traffic, so you should be quite sure that your current resources are more than enough, by a good factor, before advancing. Try to check your performance statistics for at least a week, or whatever time you think is representative. If CPU and RAM are always at 10% or less, I'd say you can safely go to half your current resources.

     

    Also, when removing resources, be wary of vCMP guests with only 1 vCPU. I make it a point of never using those for production environments, even in low traffic conditions.

     

    Mike

  • Hi Mudassar,

     

    Easy part first - adding resources will very likely NOT have a negative impact. The worst thing I can see happening is having some strange behavior on traffic distribution and persistance due to CMP (https://support.f5.com/csp/article/K14358). This can be more evident if the amount of traffic is relatively low.

     

    Now, if you remove resources, I'm going to say it depends. Less resources mean less capacity to process traffic, so you should be quite sure that your current resources are more than enough, by a good factor, before advancing. Try to check your performance statistics for at least a week, or whatever time you think is representative. If CPU and RAM are always at 10% or less, I'd say you can safely go to half your current resources.

     

    Also, when removing resources, be wary of vCMP guests with only 1 vCPU. I make it a point of never using those for production environments, even in low traffic conditions.

     

    Mike

    • Mudassar's avatar
      Mudassar
      Icon for Altostratus rankAltostratus

      Thanks

      My questions now would be that when removing resources would it also have impact on drive space? Like is there any chance of getting the image corrupted?

      • Mike757's avatar
        Mike757
        Icon for MVP rankMVP

        What? No, I don't think there's any chance of that ever happening. When you change CPU allocation, RAM allocation is also dinamically calculated, but the virtual disks remain the same.

         

        There are some procedures to reallocate disk resources, but you may have to do that only after an image upgrade - https://support.f5.com/csp/article/K15915.

         

        Mike