Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [vcpu]

The tag has no usage guidance.

1
vote
0answers
12 views

processor type differences between elasticache instance types , will all instances suffer the same way?

This may sound like yet another, "what is a vcpu" or "should I use elasticache, remember its single threaded!!" question --- but I think this asks a question unanswered. redis is single threaded, ...
2
votes
4answers
72 views

How does the vCPU align with the CPU? (VM with more cores than the CPU has)

I have a VM running on vSphere 6.5.which has 24 vCPU's. The server has two physical cpu's (xeon e5-2699 v4) which have 22 cores and hyperthreading is enabled. How exactly are the vcpu's running on ...
0
votes
1answer
26 views

aws ec2 t2.small vs t2.medium CPU performance

Since t2.medium has 2 VCPU and t2.small has 1 VCPU would it be faster as a web server? (Apache/php). I am wondering if I upgrade if I will gain any performance benefits.
1
vote
0answers
37 views

Will More vCPU's and RAM Help Protect Against Some Smaller Scale DDoS Attacks?

Obviously having more vCPU's (virtual CPU's) and more RAM by them self won't be able to alone help stop and/or prevent a DDoS attack, but let's say after a DDoS attack is finished and/or slowing down ...
1
vote
0answers
48 views

Performance on Pinned CPU cores versus automatically managed?

I have a XenServer 7.5 environment where I'm running a single Windows VM with 16 total vCPU's. My server has dual Xeon E5-2620v4 CPU's with 8cores/16threads each clocked at 2.1GHz nominal and a Max ...
3
votes
2answers
209 views

Can the number of CPU cores be reduced for a CentOS virtual machine?

Our VMware admins tell me that we can add additional virtual CPU cores to our VM's, but they tell me that we can't reduce the number of virtual CPU cores. One recently stated, "CPU on the other hand ...
0
votes
1answer
3k views

Maximum number of virtual CPU for Windows 7/10 virtual machine

For a virtual machine running Windows 7/10, is there a maximum number of virtual CPU a hypervisor can assign to it? As hypervisor, consider VMware ESXi 5.5 or 6.0. Andrea
3
votes
2answers
55 views

How to project / measure physical host wait with multi-core guests in ESXi

I’ve heard that if you have a guest with N virtual cores under ESXi, the hypervisor waits for N total logical processors on the host to become available simultaneously before delegating work from the ...
1
vote
1answer
27 views

Analyze single CPUs activities instead of sum of total CPU for what is usefull for?

I'm building a monitor to track down all Linux /proc data that can be usefull to understand how the server is behaving. Still I cannot understand if I should track every single CPU (and in a virtual ...
1
vote
1answer
306 views

Best VMWare Esxi CPU Resource Allocation Policy

We have a machine with an 88-core CPU in our department. Imagine there are 11 researchers who want to use the machine whenever they have to test a new approach. We've made 11 VMs on VMWare ESXI host, ...
0
votes
2answers
938 views

Microsoft Azure threads per core

I am looking at the Pricing guide for Microsoft Azure. https://azure.microsoft.com/en-us/pricing/details/virtual-machines/windows/ How many threads are working in the "F16" "Compute Optimized" ...
0
votes
1answer
244 views

VMWare Physical CPU to vCPU

We have VMWare hosts with 2 cpus each (that are hyperthreading). We freed up some licensing (2 core licenses) for SQL server and want to upgrade from 4 to 6 cores. From my understanding, for SQL ...
0
votes
1answer
395 views

Decreasing CPU allocation to running Guest Windows server

I have Ubuntu 16.04 as host and windows server 2012 as the guest installed using Virtio drivers in KVM. I am able to increase the CPU while guest is running, however I am not able to decrease the CPU'...
12
votes
1answer
1k views

KVM Host with 88 physical cores uses only 14 on 64 core Guest

I do have a server with 2 CPUs (22 Cores each plus HT). I created a KVM Guest with 64 allocated cores. When I run a compilation task the virtual machine shows all 64 cores at 100% (at moderate Disk I/...
3
votes
2answers
445 views

Configuring a 1-to-1 allocation of virtual processors

I have a question regarding a recommendation for setting up vCPU on a hyper-v virtual server. Documentation for the application states "For best performance, configure a 1-to-1 allocation of virtual ...
2
votes
1answer
986 views

Oversubscription vs Over allocation of vCPU resources in vSphere

I'm trying to understand over allocation of vCPU compared to over subscription of vCPU. For the purposes of the question lets assume the host that I will be using has a 16 core Xeon(2.1Ghz). Based ...
6
votes
3answers
2k views

VMware / SQL - physical vs logical cores - how many vCPUs to assign when HT is enabled

We have a ESX host: It has 2 CPU x 8 cores each, and HT enabled. So, total 16 physical cores or 32 logical cores. It has a single dedicated SQL VM on it (no other VMs run on this host), and it has ...
0
votes
0answers
186 views

CPU & Memory Reservation in vSphere & Numa concept

by googling/studying vSphere documentation I have found the possibility to use "Reservation" concept in vSphere. What it is not clear to me is : CPU and Memory reservations are configured separately ...
0
votes
1answer
52 views

Does turning off vCPU in Ubuntu 14.04 impact vmware's cpu scheduler?

I have a Ubuntu VMWare VM that was given 6 CPUs, but rarely sees a load above 1. It is running in a vSphere 5.5 cluster. Nowing that VMWare's CPU scheduler has to clear 6 CPUs for processing this VM,...
3
votes
1answer
821 views

Calculation of virtual resources

I virtualized a server using VMware ESXi. My virtual machine has 8 vCPU, while the real processor is an Intel Xeon E5-2620 v3 (6 core) @ 2,4 GHz. In order to estimate virtual resources needed for ...
2
votes
1answer
1k views

t2.micro instance is always below baseline CPU usage but still consumes CPU credits - why?

I have a t2.micro instance running Ubuntu Linux on ec2 in Ireland, it's running batch jobs and I've tuned them so that the max CPU is pretty low - it never exceeds 10%. The docs say that: When a ...
-2
votes
1answer
2k views

How vCPUs are calculated?

Yesterday I contacted my vendor to buy a server, and I asked them how I should calculate the CPU and RAM requirements for my server, given that I want to create multiple virtual servers on it He said ...
2
votes
3answers
71 views

How can I keep a third-party cloud provider accountable for guest VM performance?

I support an ERP system for a manufacturer. We're experiencing intermittent application performance issues on our database, hosted on VMware by a third-party cloud provider. (They're a smaller ...
2
votes
1answer
2k views

CPU frequency governor for virtualized guest in VMware

CPU frequency governor can scale the CPU frequency up or down in order to save resources. In a physical server usually have sense, but I don't know if this is applicable for a virtual guest running ...
0
votes
1answer
207 views

Xen reduce VCPU

I am trying to reduce the number of VCPU on Dom0, but not understanding why its not reducing the number. Log: [2016-02-11 13:43:25 2550] INFO (XendDomainInfo:1977) Set VCPU count on domain Domain-0 ...
0
votes
0answers
425 views

XenServer 6.2 VM Performance (SSD, RAID-10, Quad-core)

Greetings everyone :) My configuration is the following: HP C3000 tower enclosure 1st HP Proliant BL460 G1 quad core xeon 2.66GHz 12MB L2 cache, 24GB RAM, BIOS I15 5/2/2011 partnered with HP ...
1
vote
2answers
266 views

What does take all the cpu here?

On a small SSD VPS I got 2 GB of RAM and 2 vCPU core (dedicated to my server), virtualized via KVM. So far so good. The server is mainly used for databases (MySQL) and fast network file storage (via ...
16
votes
3answers
119k views

Understanding the VMware ESXi limitations of the free Version

I am running an ESXi Vsphere Client Version 6.0.0 but with all the different documentation and changes I have trouble to understand my limitations. From the official documentation I see that my limit ...
0
votes
0answers
113 views

VPS Server shoots to 900% CPU Utilisation for 10 to 15 minutes

I've just taken a VPS Server with Assured 1 core AMD opetron and burstable to 8 cores. RAM is 5 GB Average Usage so far been around 1 Cpu, but at a point of time - when checked through monitoring - ...
1
vote
2answers
3k views

Virtualization: vCPU pinning with Hyperthreading Host CPU?

I'm using KVM/libvirt on a Linux server with Core i7-2600 CPU, which has the following CPU topology (1 Socket, 4 Cores, 8 Threads): Physical | Logical ---------+-------- Core 0 | 0, 4 Core 1 | 1, ...
2
votes
1answer
4k views

How to assign dedicated vCPUs to specific VM on Proxmox (KVM) or what system could do that?

I'm posting this here, because what I've found about the topic is either outdated, incomplete or not suitable for various reasons. I have wanted for a long time to learn how to map specific vCPUs to ...
0
votes
2answers
140 views

CPU core utilization is automatic?

I have a 512MB KVM Debian OS VPS running several game servers and several sql enabled websites. Currently I have 1 vCPU core and it stays around 15% usage. If I were to get an extra vCPU core will ...
5
votes
1answer
3k views

AWS EC2 instance hyperthreading

I am currently doing some performance testing of web-apps that we have moved to AWS. One of the things we have noticed is that vCPU performance doesn't seem to be nearly as good as we'd expected. In ...
-2
votes
1answer
121 views

KVM vCPU: Creating VPS with more GHz

I was trying to find a suitable answer to my question about if it is possible to create 2 x 3 GHz guest on a host server that has 6 cores running at 2 GHz. As I understood I would have 12 GHz total ...
1
vote
2answers
490 views

Single virtual machine in ESXi with all cores assigned

I have this 2 CPU server (2x4 = 8 cores in total) in which I plan to put a single W2012 virtual machine. Is it a good idea to configure 8 vCPU for the VM or should I leave spare cores to relief ...
2
votes
1answer
1k views

How can an ESXi have 1 core and 4 sockets?

I know this is in reference to a vCPU, but even so, logically it doesn't make sense to have 4 sockets and a single core. That sounds to me more like you've filled one of the sockets with a single ...
-1
votes
1answer
229 views

vSphere CPU/vCPU Performance [duplicate]

This might be a rookie question but if I'm currently on a 4:1 oversubscription of my CPU ressources does that mean that my processors performances are divided(splitted) into 4 lower perf. vCPU? Will a ...
1
vote
1answer
795 views

KVM: How to update amount of cores/procs during runtime

The title says it all. How do I increase the amount of cores/cpus of a vm without requiring a reboot. Strangely I did not find any documentation of how to do this...
2
votes
1answer
1k views

virsh vcpu_period and vcpu_quota

I have been looking into ways to divide my CPU amongst KVM guests other than by just setting vCPU access limits. I understand the concept of cpu_shares which can be set/displayed with virsh schedinfo, ...
1
vote
1answer
4k views

How does vCPU in VMware vSphere works? [closed]

I would like to know how vCPU works and how its "connected" to the real CPU - how ESXi manages real CPU hardware resources to satisfy vCPU needs? Does vCPU uses all available cores, multithreading, ...
-8
votes
2answers
412 views

Physical server to vCPU`s [closed]

I have the following server: Processor: AMD 12 Cores RAM: 32GB Storage: 2x500GB How many vCPU`s can I create using VMWare ESXi or VirtualBox ? Any other product that you think I should know ? Any ...
0
votes
3answers
85 views

Notification for high vCPU Usage

At the moment I'm using a third party tool (vmturbo) which allows me to monitor the vCPU usage on my VMs. I've been wondering however if there's any method built inside of VMware or through powerCLI ...
0
votes
1answer
1k views

VMware ESXi/vSphere Fault Tolerance vCPU Limit

So I am aware that VMs in FT mode are limited to a single vCPU. Is it possible to assign multiple cores to the single vCPU, and still have the VM support FT mode? Or are you forced to use both a vCPU ...
2
votes
2answers
3k views

VMware - Can a 1 vCPU VM use more than 1 physical core at the same time?

Assume I have a physical ESX host with ONE quad-core processor and hyper-threading disabled. This means it has a total of 4 physical cores or pCPUs. I create a single VM on this VMware host. I assign ...
1
vote
2answers
891 views

Windows Server 2012 Hyper-V bad vCPU performance

we have a windows server 2012 enviroment with two hyper-v servers. Each of them has two 16 Core AMD CPU's, eight 16GB DDR3 ECC RAM modules, 10 HDD's in HW-Raid 6. Now Hyper-V is running and some VM'...
26
votes
4answers
134k views

Best Practice: vCPUs per physical core

I am trying to find some documentation or best practice guides for virtualization with respect to provisioning vCPUs per physical core (of a CPU). If it matters, I am looking at vmWare for the ...
0
votes
1answer
424 views

how do I add a vcpu to one of my KVMs in QEMU?

I want to add a vcpu to a virtual server in QEMU. I tried editing the XML file in /etc/libvirt/qemu and starting the server, but that does not seem to work.
1
vote
2answers
3k views

Can KVM CPU assignment count differ from physical hosts CPU count?

I have read this question. I knew already that I could for example, have a quad core machine with four guests each having two vCPUs. As they don't all be require 100% CPU usage all the time, the ...
1
vote
2answers
218 views

Optimum amount of vCPUs for IIS7.5 application (ESXi 4.1)

CPU Ready time is really low on my physical server, however ASP.NET(2nd) application is not running fast. VM has 1 vCPU and 12GB of memory where only 6GB is used. Sometimes when team starts working ...
4
votes
1answer
1k views

Modifying the number of VCPUs in a VMware VM

In ESXi, what is the automation/script (I expect it would be using PowerCLI somehow) approach to modify the number of VCPUs in a VM? In context, when using our kickstarts, RHEL won't install the SMP ...