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1 quad core processor means how many CPUs in ESX 4i?

Hi All,

I have installed ESX4i on one of a blade server. Server has one quad core processor in it. When I installed ESXi it is showing as in attached image.

May be I am wrong but I was expecting to see 4 CPUs with 1 Quad core CPU which I can assign to 4 VMs.

Can any body confirm it that 1 quad core processor means 4 cpu or 2 cpu in ESXi?

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Shaun
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If you ONLY have ONE physical processor in your computer then it is a single processor. This meads that it has 4 cores and can process 4 tasks cconcurrently.

In terms of guest operatings systems perm core. VMWare can conservatively support 6-8 guest operating systems per core or 24-32 guest operating systems per processor.
According to your screenshot, you have 1 DUAL-CORE processor (not Quad). You will notice in your screenshot that it says 'Processory Sockets   1'. That means you have 1 physical CPU socket populated on your motherboard. Where it says 'Logical Processors   2' in your screenshot, that refers to your CPU being a DUAL CORE single CPU. If you enable hyperthreading in your BIOS (it's disabled according to your screenshot), you can double your CPU logical processors to 4 total.

In retrospect to what "nappy" mentions, I've only heard you can run about 4 VMs per core, but I don't recall seeing anything specifically/explicitly documented saying so. (I'll post documentation if I come across it) If you were to enable hyperthreading on your system, you would be able to run about 16 VMs comfortably. Now, depending on the guest OS, apps within the OS, and the resources they require, that number may be less....or even more. Keep in mind it's just an 'estimate'.

Hope that helps.

Regards,
~coolsport00
Oh...and to answer your 2 questions specifically:

1. You can run 4 VMs very comfortably on your system, well, depending on how much memory you have in your ESXi host. I recommend, for 4 VMs, you have 16 GB minimum. Not knowing what guest OS your VMs will be, the apps in them, etc., plus accounting for memory required by the ESXi host and some extra RAM to expand, that is a good starting point.

2. You are correct -> QUAD CORE = 4 LOGICAL processors (not physical or sockets). A Quad Core is a single CPU socket, with 4 Cores within it. A Dual Core is 2 logical processors within a single CPU socket, etc. Now again, if you enable hyperthreading, your logical processor count will double. You can read more about hyperthreading in the Resource Mgmt Guide from VMware:
http://www.vmware.com/pdf/vsphere4/r40/vsp_40_resource_mgmt.pdf (pg. 17-18)

Regards,
~coolsport00
The sweetspot is 4.  You can get 8-10 and this PDF says alot different http://www.vmware.com/pdf/vsphere4/r40/vsp_40_config_max.pdf
Thanks for the doc, but I didn't see where it says how many VMs per core. I saw VMs per host, cluster, volume, etc. Did I overlook it? Thanks "nappy_d" :)

~coolsport00
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Member_2_231077

E5506 is quad core and doesn't support hyperthreading. It's possible the cores are disabled in BIOS but unlikely. I suppose it could be set to lock-step mode as well although I think it only appears as a single core in that case.
I went with the number of vm's perhost.
This URL confirms that its a Quad Core CPU.

http://tinyurl.com/268qmuw - Intel® Xeon® Processor E5506

It does not support Hyper-Threading.

Typically vCPU : pCPU ratio is defined as 4vCPU : 1pCPU, where vCPU stands for virtual CPU and pCPU for physical CPU.