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vmware vista guest only seeing 2 out of 4 cores

Hoddi1
Hoddi1 used Ask the Experts™
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Hi all
i am running windows vista x64 on a esxi vmware server i have assigned it 4 proccessors but for some reason it only seems to be using 2, see attached screenshot
any ideas how i can fix this ?
winvistacores.PNG
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JohnBusiness Consultant (Owner)
Most Valuable Expert 2012
Expert of the Year 2018

Commented:
Vista can only support 2 processors just like XP. That is the reason. ... Thinkpads_User
Gary CaseRetired
Most Valuable Expert 2013
Top Expert 2009

Commented:
Both XP and Vista will use all the available cores ==> 4 cores for a quad core CPU,  8 "cores" for an i7 quad core with hyperthreading ... so that's NOT the issue.

Hoddi1 ==> the processor assignment tab only shows 2 CPUs selected ... does it give you the option to assign 4 ??
JohnBusiness Consultant (Owner)
Most Valuable Expert 2012
Expert of the Year 2018

Commented:
@garycase - Thanks. I was looking at number of CPU's and not number of Cores.

@Hoddi1 - VMware Workstation allows you to set number of CPU's *and* number of Cores per CPU, so make sure both variables are set correctly. ... Thinkpads_User

Author

Commented:
The proccessor assignement only gives the option of 2 cpu, it was unmarked but i marked it just to take the screenshot,
any ideas ?
JohnBusiness Consultant (Owner)
Most Valuable Expert 2012
Expert of the Year 2018

Commented:
What version of VMware are you using? I am using VMware Workstation 7.1

Here is a screen shot of the relevant VMX settings. This is where you need to set it and before looking in the guest when it is running.


VMware-7-with-Vista.png
Gary CaseRetired
Most Valuable Expert 2013
Top Expert 2009

Commented:
I don't have esxi installed, so can't look at the actual CPU assignment screens ==> but if it only allows you to set 2 processors, that's all you can do.

VMWare improved their CPUs/cores settings with WorkStation v7  ==> prior to that it only allowed setting "number of processors" ... which was actually the number of cores;  but with v7 you can set both the # of processors and the # of cores for each of those processors (subject, of course, to what's actually available on the host).

Commented:
What is your processor?  If you have an Intel i7, then you have "threads" in addition to cores and some software will display the threads as cores.  For example, if you have an i7 quad core, some software will show 8 cores, when you actually have 4 cores running 2 threads each.

i7 processors use hyper-threading, giving each core 2 threads, which makes it look and act like double the number of cores you actually have.  

Author

Commented:
Hi
you can see the proccessors in the screenshots above
Intel Xeon E5520

i also have a windows XP machine running on the same Esxi host that only seems to utilize only 2 cores of 4 cores that are visible in device manager
JohnBusiness Consultant (Owner)
Most Valuable Expert 2012
Expert of the Year 2018

Commented:
You are probably stuck with what you have because of ESXi. The free tools never do as much as the paid tools, so this is not at all surprising.  ... Thinkpads_User

Author

Commented:
well on the same ESXi server there are also a couple of windows 2008 servers and they are using 4 cores succesfully, only windows vista and xp use 2
JohnBusiness Consultant (Owner)
Most Valuable Expert 2012
Expert of the Year 2018

Commented:
That may be, but Server 2008 is a totally different OS than XP (miles apart) and very different from Vista. Since ESXi is not showing you these options (paid VMware Workstation does), then it is probably an OS capability to use the cores. ... Thinkpads_User
ESX or ESX1 (free or not) uses a core as a virtual CPU or vCPU. When you assign a vCPU to a VM you are assigning a core of a CPU.
Awarded 2009
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Commented:
This question has been classified as abandoned and is being closed as part of the Cleanup Program. See my comment at the end of the question for more details.