Initially, I don’t know why I am posting this article because this will make some redundancies to other contents in the internet. Hmmm, well maybe because some customers always ask me about the data sheets of VMware products, then I think it will be easier if I just tell them about this post rather than they google it and download them one by one.
VMware Bundle Components Datasheet:
– VMware vCloud Suite Datasheet : (Download Here)
– VMware vRealize Suite Datasheet : (Download Here)
– VMware vCloud NFV : (Download Here)
VMware per-product Components Datasheet:
– VMware vSphere : (Download Here)
– VMware vCenter : (Download Here)
– VMware vCloud Director for SP : (Download Here)
– VMware vRealize Automation : (Download Here)
– VMware vRealize Operations : (Download Here)
– VMware vRealize Business for Cloud : (Download Here)
– VMware Site Recovery Manager : (Download Here)
– VMware NSX : (Download Here)
– VMware vSAN: (Download Here)
Notes: there are still other offers from VMware such as Cloud Foundation, vSphere Integrated Containers, vRealize Code Stream, vSphere Integrated Openstack, vRealize Log Insight, vRealize Network Insight, Workspace One, Horizon, Airwatch, etc (… please refer to http://www.vmware.com for more detail).
After reading this post, now maybe some of you just know that VMware is not just vSphere ESXi + vCenter right? 🙂
Yeah, it’s the Software-Defined Data Center
VMware, a global leader in cloud infrastructure and business mobility, accelerates our customers’ digital transformation journey by enabling enterprises to master a software-defined approach to business and IT. With VMware solutions, organizations are improving business agility by modernizing data centers, driving innovation with modern data and apps, creating exceptional experiences by mobilizing everything, and safeguarding customer trust with a defense-in-depth approach to cybersecurity.
In this post, I would like to share about CPU limit and CPU reservation configuration in vSphere ESXi virtualisation technology.
Actually those features are great (since the configuration also available in vCloud Director (*it will call the configuration in vCenter)). Those features are great if you really know and already consider on how to use it properly. For example, if you would like to use CPU reservation please make sure that you are not running those VMs in a fully contention/overcommitment environment. For CPU limit, if you have application that is always consume 100% of CPU even though you always give more CPU to the VM – then you can use Limit configuration to limit the usage of the CPU by that application (but, for me the Best Way is ask your Developer to Fix the Application!).
Okay, let’s talk more about CPU Limit.
Duncan Epping and Frank Denneman (both are the most respectable VMware blogger), once said that: “Look at a vCPU limit as a restriction within a specific time frame. When a time frame consists of 2000 units and a limit has been applied of 300 units it will take a full pass, so 300 “active” + 1700 units of waiting before it is scheduled again.”
So, applying a limit on a vCPU will slow your VM down no matter what. Even if there are no other VMs running on that 4 socket quad core host.
Next, let’s talk more about CPU Reservation.
Josh Odgers (another virtualisation blogger) also explained that CPU reservation “reserves” CPU resources measured in Mhz, but this has nothing to do with the CPU scheduler. So setting a reservation will help improve performance for the VM you set it on, but will not “solve” CPU ready issues caused by “oversized” VMs, or by too high an overcommitment ratio of CPU resources.
The configuration of Limit and Reservation are done outside the Guest OS, so your Operating System (Windows/Linux/etc) or your Application (Java/.NET/C/etc) do not know that. Your application will ask the resource based on the allocated CPU to that VM.
You should minimize the use of Limit and Reservation as it makes the operation more complex.
Better use the feature of default VMkernel which already got a great scheduler functionality that will take fairness into account. Actually, you can use CPU share configuration if you want to prioritise the VM other than others.
But, the most important thing is: “Please Bro…, Right Size Your VM!”