Scenario: An infrastructure team has stated that the new Citrix Virtual Apps and Desktops virtualization host will have the specifications shown in the exhibit.
Click the Exhibit button to view the specifications.
The design document calls for the VMs to have 2 CPUs and 4 GB RAM.
Approximately how many virtual desktops can be hosted an each physical server?
To determine the number of virtual desktops that can be hosted on each physical server, we need to consider the given resources and the specifications for the virtual machines (VMs). Each VM requires 2 CPUs and 4 GB of RAM. The host machine has 4 sockets, with each socket containing 12 cores, and also has hyper-threading enabled. The total amount of RAM available is 512 GB. Given that there are 4 sockets each with 12 cores, this results in a total of 48 physical cores. Considering hyper-threading, this gives a total of 96 logical cores. However, each VM requires 2 virtual CPUs, translating to each VM utilizing 2 logical cores. Therefore, the number of VMs that can theoretically be hosted based on the CPU is 96/2, which equals 48 VMs per logical CPU capacity. But memory is also a limiting factor. Since each VM requires 4 GB of RAM, the total number of VMs that can be hosted based on the RAM capacity is 512/4, which equals 128 VMs based on RAM capacity. Hence, the actual limiting factor here is the CPU, which allows for a maximum of 120 VMs based on the available logical cores (considering a little overhead for the host itself). Therefore, the best choice among the options given is 120 virtual desktops.
12 physical cores (are they? the question doesnt state if HT is on or off exactly) but the answer is C. 120. 12cores with HT OFF: 4 sockets, so 4X12core CPU's Apply the rule of 5 VMs per physical core when the size is 2vCPU/4GB and you would get: 4x12x5=240 (answer B) However, we only have 512GB in server 240x4=960 (Answer B is wrong) 512GB/4GB= 128VMs: ANSWER C. 120 is correct And now 12cores with HT ON, so we only 6 physical cores. 4 sockets, so 4x6core CPU's Apply the rule of 5 VMs per physical core when the size is 2vCPU/4GB and you would get: 4x6x5=120 120x4=480GB RAM ANSWER C. 120
Total number of cores is 4x12x5=240 Based on example 1 and the note to ignore memory the answer I think is B https://docs.citrix.com/en-us/tech-zone/design/design-decisions/single-server-scalability.html#scalability-factors
I think question is about RAM calc, not CPU and some magic number of it) C is correct 512/4= 120
Im not so sure that you can ignore memory in this case. In the example 1 given. Each host has 768Gb memory which satisfies requirements from the X5 multiplier (180 X 4Gb = 720Gb). But in the question you are way overcommitting memory with answer B:240 as Eximius pointed out. I think it would only be reasonable to presume a minimum 60% idle ratio from Citrix article which would still leave the RAM in effect at 853Gb (and not 960Gb) 60% of 853GB = 512GB. I will go for C: 120 but I'm not sure that the answer could not be A:190. With 190 X 4Gb = 760Gb as that would satisfy the requirement of 60% RAM idle,
this question is meant to trick us. Think no CPU calc is needed. Only RAM! And that is easy 512 : 4 = 128 ...so C is correct!
12 physical cores + magic multipliers: 5x12=60 so D is correct.
I agree with this answer. From the doc: " Although hyper-threading, clock speeds, and virtual cores are all important, nothing is more important than the number of physical cores on a server"
I think question is about RAM calc, not CPU and some magic number of it)
If it would be 12 cores in total you would go for a Triple-Core CPU. Unlikely ...
answer C Note it says "hyper threading", so devide 12/2 =6 physical cores now apply citrix recommended formula according to the article: https://docs.citrix.com/en-us/tech-zone/design/design-decisions/single-server-scalability.html#the-magic-multipliers 4 sockets * 6 physical cores * 5 CVD = 120 CVDs if you want to calculate for apps (not part of this questions): 4 sockets * 6 physical cores * 10 CVA = 240 CVA
C. 120
C is right 512/4= 120
512GB/4GB= 128VMs: ANSWER C. 120 is correct
There are some assumptions being made here, but I think it's safe to assume they mean there are 12 cores PER SOCKET so gh1 is correct. The math is 4x12x5=240. B is the correct answer. Nothing else factors in. Total cores on the box X 5 for VDI. Total cores on the box X 10 for RDSH. That's it.
Dont we have to divide 240 by 2 as the VMs should have 2 CPUs each to result in 120 VMs and C as answer?
I think question is about RAM calc, not CPU and some magic number of it) C is correct 512/4= 120
I believe this question is about cpu and not memory. It is very well possible to run 150 desktop VM's with 4GB of RAM on a host with only 512GB of RAM in it. We do is also in our environment. It is not possible when you have (NVIDIA) GPU integration. But in thsi scenario it is very well possible. Because it states 4 sockets, 12 cores with hyperthreading, I believe they mean 4 physical CPU's (and all CPU's have hyperthreading these days) so when they say 12 cores with hyperthreading, they mean 12 cores with hyperthreading "on". So the 4 physical CPU's have 6 cores is 4x6x5=120 VM's. Answer C is then the correct answer.