[Decent12]

Hey, i am just wondering what is basic difference between openvz and kvm and as far as i noticed openvz does not eat lot of memory.
i got a question aswell kindly answer that aswell.
Q1: does openvz will affect my game servers performance? and why everyone prefer kvm if openvz eats lesser memory?

[chanalku91]

Hey, i am just wondering what is basic difference between openvz and kvm and as far as i noticed openvz does not eat lot of memory.
i got a question aswell kindly answer that aswell.
Q1: does openvz will affect my game servers performance? and why everyone prefer kvm if openvz eats lesser memory?

The difference is clear in terms of usage!

On OpenVZ you use Shared Resources! If you exceed the normal VPS usage you can be suspended! On KVM you will get dedicated Resources!
KVM is more reliable than OpenVZ because at OpenVZ if other VPS experience High CPU usage and Performance is Decreasing your VPS will get the impact too!

[Mashiro]

OpenVZ: Software virtualization based on the use of containers to isolated the VMs from each other. All resources are fully shared between all VMs and the host system and heavy overselling is possible. Vital and critical system processes are running on the host node and don't run inside the hosted VMs (hence why the OpenVZ VM memory usage is much lower vs KVM). Heavily crippled in regards of real world features (firewall modules are mostly disabled and only a small part can be enabled by the host node administrator for the VMs, no real virtual disk and filesystem and many other things). However this virtualization technology comes with tiny to no performance loss vs hardware virtualization like KVM.


KVM: Hardware virtualization that emulates a real machine inside a VM from BIOS to pretty much everything else. Resources here are / can be allocated to the VMs directly. However that doesn't mean that overselling is not possible. There are ways to still oversell KVM but not as much as OpenVZ. The memory usage is higher because every VM runs its own system processes because the VMs are fully isolated from each other and the host system. Like you'd be running several real servers. Due to hardware virtualization you can do whatever you want. No real limitations other than what the hardware, your knowledge and / or the ToS of the provider gives (you can even pass through GPUs, full CPUs with RAM and PCI/PCIe devices exclusively to VMs). For this price you pay with a small performance hit but with todays hardware it is hardly noticeable.


This question has been asked millions of times. Google probably has so many answers and maybe even more detailed and better answers than mine. My reply is just a brief OpenVZ vs KVM and their general / basic differences. I also wonder a bit... you have been here a long time and also on FreeVPS... and you ask this question now?

[Khadeer143]

For my choice I go with KVM which is better then openvz KVM vps give good performance ,so go for KVM vps

[youssefbasha]

I would like to choose KVM & i recommend it because KVM is more dedicated than OpenVZ

[Decent12]

This question has been asked millions of times. Google probably has so many answers and maybe even more detailed and better answers than mine. My reply is just a brief OpenVZ vs KVM and their general / basic differences. I also wonder a bit... you have been here a long time and also on FreeVPS... and you ask this question now?

i have searched on google as well and had asked in freevps.us aswell i think but there were different views some of them told me that OpenVz does not use lot of memories and some told me that i should use KVM.
I was just confused till now then why people prefers KVM if OPENVZ uses less resources

[tryp4vps]

Almost everyone prefers KVM because it is a more isolated environment than OpenVZ.

Also if you want to run a different Operating System apart from Linux, for example Windows, then you have to choose the KVM virtualization​.

[Honey]

My choice would be KVM ofcourse, OpenVZ is also considered outdated now if I am not wrong(since Virmach had been moving their virtualization)

[Mashiro]

[...] OpenVZ is also considered outdated now if I am not wrong [...]

OpenVZ 6 is EOL (end of life). However OpenVZ 7 is already available and being maintained for at least the next few years. OpenVZ 7 is based on a newer kernel, has more features and is a small step closer to something like hardware virtualization while still applying the general concepts of OpenVZ container based virtualization.

OpenVZ 7 is simply not well known and only a few providers use it. KVM simply still offers way more than OpenVZ 7.

Note: https://post4vps.com/Thread-The-End-of-O...ght=OpenVZ

[fChk]

i have searched on google as well and had asked in freevps.us aswell i think but there were different views some of them told me that OpenVz does not use lot of memories and some told me that i should use KVM.
I was just confused till now then why people prefers KVM if OPENVZ uses less resources

The short answer is because those people are VM "consumers" not "producers"; hence they are more concerned with getting a real VM that they can tweak, customize and secure as it is possible. KVM virtualization offers that possiblity while OpenVZ can't. I learned this the hard way, the last time I had a VPS @Gigarocket (3/4 years ago.)

In contrast, It's the guys selling those VMs who care much about the resources that each virtualization technology need for a smooth service. Although, it's no secret that they generally prefer using OpenVZ virtualization because of the overselling aspect of it (meaning MORE PROFIT.)

Now for some theory about these 2 kind of virtualization technology, although @Hidden Refuge mentioned this already, but I want to stress on the container aspect of OpenVZ (as I worked a lot with Docker containers which is another application oriented container tech of 2013.)

I will start with KVM (Kernel-based Virtual Machine), which is generally considered as a type II hypervisor (some/RedHat consider it type I, i.e. bare metal), responsible for the "classic" hardware virtualization that allows you to run multiple, completely isolated VMs.

In contrast, OpenVZ is an OS-level virtualization software that relies on a patched version of the Linux kernel to split the physical server allowing you to run multiple isolated containers. Yes! Your VPS is just a container in this case. This is why it's lightweight resources-wise and this why resellers can oversell its VMs.

In short, OpenVZ is a "system container" platform designed to host complete guest OSes without requiring any emulation (relying only on Linux kernel advanced features in process management, security etc....)