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From Kirk Kosinski <>
Subject RE: ACS 4.3 & VMware CPU Allocation
Date Tue, 14 Jun 2016 18:56:35 GMT
Hi, you can configure the cores per socket on the template.  I'm not sure if this works in
CloudStack 4.3 but it should in 4.4 and newer. [1]  It is configured by adding a detail with
cpu.corespersocket=# to the template.  I'm not sure if this is possible in the UI, so if not,
try the updateTemplate API. [2]

Best regards,


53 Chandos Place, Covent Garden, London  WC2N 4HS

-----Original Message-----
From: Timothy Lothering [] 
Sent: Tuesday, June 14, 2016 2:49 AM
Subject: Re: ACS 4.3 & VMware CPU Allocation

Hello Community,


We have found a very interesting issue with CPU allocation in ACS 4.3 and VMware. When a Service
Offering is configured, you can choose the number of Cores and clock speed, which is simple
enough. The problem comes in on HOW the cores are assigned.


In VMware at least, each core is assigned as a vSocket, with 1 vCore. As an


1.     Service Offering defined is 8 Cores @ 2.5GHz,

2.     Instance is provisioned as 8 vSockets with 1vCore per Socket

3.     OS displays all 8 "CPUs"

4.     Happiness!


But, when you are using Core based licensing with products such as Microsoft SQL 2014 Standard,
there is a limit on the number of supported "physical"
sockets, in this case, 4.


So when you run a SQL query/command, only 4 of the 8 cores are used, the only way around this
is to change the VMware settings to 4x vSockets with 2x vCores per socket. There is a performance
hit as described here:
ce.html, but the main issue is that Customers are trying to use all available resources.


My questions from the info above:


1.     Will there be future support to define vSockets and vCores per
vSocket in a future release of ACS?

2.     What is the impact on ACS Usage and Management reporting if we change
the vSockets manually? (on VMware itself)


Your insights would be appreciated.






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