Virtualization Noob

[bob4432]

just was introduced to vmware and am in love w/ it 🙂 before i get too many ideas, just how much control over the hardware does the vm have? say a machine that is capable of gaming a certain game at a certain resolution, would a vm setup be able to accomplish the same hardware efficiency? or is that not a reality?

also need to look into the networking area and how to get to each machine...i could get rid of 2 actual machines if all things work out. recommend any good reading please.

also, is vmware a good setup as i am just borrowing it from a friend or should i look at other options before i buy it? if anybody can tell me their real world experiences w/ the different virtualization software i would greatly appreciate it.

thanks

 

[boran]

VirtualBox is imho a good alternative to VmWare and it is open source and free for private use.

You will never get the same performance from a VM as your native machine. From my experience disk performance is about halved. Memory and CPU are not that bogged down, but you might loose multicore (your guest sees only a few or one of your processors)
3D graphics will be severely crippled. most of the 3d handling in VM applications is still experimental since this is a somewhat new application of the technology. (VM used to be enterprise tech mainly, the consumer applications are a recent development)

 

[Nothinman]

just how much control over the hardware does the vm have?

Virtually zero, no pun intended.

Xen lets you pass PCI devices directly to domUs (guests) but that's exclusive access so to game on a Xen domU you'd need at least 2 video cards, one for the dom0 (host) and one for the gaming domU.

say a machine that is capable of gaming a certain game at a certain resolution, would a vm setup be able to accomplish the same hardware efficiency? or is that not a reality?

Not yet. Some of the workstation targetted VM tools are working on 3D support, but it's not really usable for games yet.

also need to look into the networking area and how to get to each machine...

If you set them up as bridged they'll work just like a normal machine on the network.

also, is vmware a good setup as i am just borrowing it from a friend or should i look at other options before i buy it?

VMware is still the leader, but the different SKUs vary in capabilities. For example, Workstation lets you have multiple snapshots per VM while the free version of Server only lets you have 1.

 

[stash]

If you don't need snapshot and recording features, you can use the free VMware Player.

edit: yes, the latest version of Player allows you to create VMs.

 

[jalaram]

Virtualbox now has snapshots. I believe they can also handle 2 cores and have some 3d support.

 

[bob4432]

thanks for the info. so it sounds like i should make the actual main hosting machine the gaming rig, and then add in the others that don't need the hardware acceleration. excellent. i have found in vmware i can select the amount of processors/amount of cores on each processor/amount of ram/hdd size. looks like i will be looking for a quad that supports vt for my skt 775 board since i am trying one last upgrade w/ this machine and the machines the vms will replace aren't stressed and they are just single core 939 machines.

now, i am assuming that i would need a main/host os that supports 64bit for the addtl ram - figure i will at least 4GB but may move up to 8GB just in case. this is excellent, can get rid of a couple extra machines - less power usage, less heat and more room 🙂.

one last question, and i guess it is a rather important one - is this setup ok/stable enough for a server setup if the main hardware is stable enough?

and in regards to vmplayer - what is meant by snapshot and recording? fwiw i use camtasia for recording video when i need to make a quick "educational" video of how to do certain things that are much easier to show via a video vs explaining it out. would camtasia not work w/ vmplayer?

 

[imagoon]

VM's will only be as stable as the hosting OS. Windows can be stable, contrary to the zealots will tell you, but typically the host is used specifically for hosting vm's and nothing else at the enterprise level. At home it is a bit looser and the biggest stability issue will be windows itself as your running on home hardware.

Gaming machines seem to the least stable so if your game bombs the machine you just lost your host which will kill the virtual machines. Obviously if you only boot them when needed then that no longer matters. Running VM's can also rob you of some decent horse power while gaming so expect your games to randomly stutter and lag because the CPU is being diverted elsewhere.

With the proper hardware, VM's can run very close to native speeds.

As a side note I support ESXi4.0u1 running on a pair of Dell R610's @ about 5:1 hanging off of a 15 SAS disk SAN at the moment. So take that at what you will.

 

[bob4432]

good points, hell maybe i will throw a game in a vm and see how it goes. it can't hurt...but i do need a cpu that support virtualization correct? atm i am just running a e2160 @ 3.0GHz and i don't believe that supports virtualization. i do have a am2+ machine that has a 5000 in it that supports virtualization and enough gpu hp for its monitor which is only 1280x720, and it has win7 x64, so maybe i will put a vm on it and see how that goes....decisions, decisions

 

[Nothinman]

i have found in vmware i can select the amount of processors/amount of cores on each processor/amount of ram/hdd size.

Yes, but stick with 1 core per VM. I've read that adding more than 1 vCPU can cause performance problems unless the load is just right. Not sure if that's just ESX or not though.

now, i am assuming that i would need a main/host os that supports 64bit for the addtl ram - figure i will at least 4GB but may move up to 8GB just in case. this is excellent, can get rid of a couple extra machines - less power usage, less heat and more room

If the host will be a Windows client OS, yes 64-bit would be required. If it's something else you could probably get away with a 32-bit OS. But 64-bit would be better all around.

one last question, and i guess it is a rather important one - is this setup ok/stable enough for a server setup if the main hardware is stable enough?

For performance Windows as a host seems noticeably slower than Linux to me in I/O, but you'll probably be fine. For stability, you're at the mercy of the host OS's drivers so as long as they're fine you'll be fine.

and in regards to vmplayer - what is meant by snapshot and recording?

Snapshots are kind of like disk images. When you tell VMware to take a snapshot it saves the VM state and starts making changes to another file. Some time later you can revert to that snapshot and undo everything that's happened since then.

I'm not sure about the recording, but I wouldn't be surprised if newer versions of VMware Workstation let you record the console session to a video.

 

[bob4432]

thanks again all. is vmware the way to go? how about win2008 w/ hyper-v? just want to make sure i start off on the right foot even if there is a longer learning curve or $$ but would rather do it once right then many wrong

 

[imagoon]

thanks again all. is vmware the way to go? how about win2008 w/ hyper-v? just want to make sure i start off on the right foot even if there is a longer learning curve or $$ but would rather do it once right then many wrong

I am vested in VMware. Mostly because they have far better enterprise tool kits and is generally better performance on the same hardware. This might not stay this way but that is what I see now. Hyper-V has potential also and you may see smaller shops using it because the perceive it as cheaper. It is but you can get a the 3 server / 2 cpu vmware licenses for $750 so it is almost nothing and they had to buy windows itself anyway.

Much of the theory of virtualization applies across all of the platforms. RAM and Disk I/O will often be king, CPU has to be able to support it also. However a slower CPU with more RAM and faster disks will generally give you better results.

ESXi can run diskless with less effort than Windows. Basically ESXi is small enough to be able to boot and load the entire machine of a 1 gig USB stick while Windows would need to delve in to SAN luns and the like.

I would definitely go with 64-bit. ESXi4 is 64-bit from the ground up, Hyper-V will just run better period in 64-bit. Also the VT extensions in processor is typically required to run a 64-bit host. They also greatly enhance all of the hosts performance.

It really depends on what you are doing. If your doing this for fun versus running a business on it. Remember you have to pay for the Guest OS's. So at the very least you have to buy 1 2k8 standard license for Hyper-V for the host OS which will also grant you 1 guest 2k8 license. The key here is that you cannot use the host OS for anything other than hyper-v so toss out any 'gaming'.

The one CPU thing that Nothinman mentioned is true. When you have 2 mostly idle virtual cpus, a lot of performance is lost keeping the virtual CPU caches and the like in sync. This makes a two cpu system feel a bit slower because a lot of the threads are running on one core. In general your better off running 1 core @ 90% all day than 2 @ 45% in the guest. RAM is easy as your just dividing it up as needed, disk is the same thing as it is just a file on the underlying filesystem.

Anyway both are good options depending on your needs. I personally went VMware for the features and the performance.

 

[Nothinman]

CPU has to be able to support it also.

Not true for VMware, at least for 32-bit guests.

I would definitely go with 64-bit. ESXi4 is 64-bit from the ground up, Hyper-V will just run better period in 64-bit. Also the VT extensions in processor is typically required to run a 64-bit host. They also greatly enhance all of the hosts.

Except that using ESXi would kill his ability to game on the machine. Installing the Hyper-V role on Windows probably introduces it's own set of restrictions, but I don't know what they are.

And while I agree that going 64-bit shouldn't even be a question, I don't know how that will "greatly enhance all of the hosts".

The one CPU thing that Nothinman mentioned is true. When you have 2 mostly idle virtual cpus, a lot of performance is lost keeping the virtual CPU caches and the like in sync. This makes a two cpu system feel a bit slower because a lot of the threads are running on one core.

I also just read somewhere that if you give a guest >1 vCPU VMware will wait until that many cores are idle before doing something on that guest to ensure that it gets both CPUs. I can definitely see how that would be a problem unless you've got cores to dedicate to a VM.

 

[imagoon]

Not true for VMware, at least for 32-bit guests.

I meant you still need enough CPU to support the machines. Trying to run 8 vCores with and expected load of 80% per vCore on a dual physical core is heading towards a world of hurt no matter how many terabytes or RAM or terabits / sec of Disk I/O you throw at it.

Except that using ESXi would kill his ability to game on the machine. Installing the Hyper-V role on Windows probably introduces it's own set of restrictions, but I don't know what they are.

I am aware of the gaming. That is why I asked him what he is emulating. Hyper-V licensing prohibits the use of the Host machine for anything other than Hyper-V if you want to use the hardware license as a virtual license. So installing the DNS role on a Hyper-V machine with 1 2k8 guest would = 2 license needed where as removing DNS from the host would revert it to 1 license.

And while I agree that going 64-bit shouldn't even be a question, I don't know how that will "greatly enhance all of the hosts".

VT extensions are night and day difference in performance on ESX(i) on all hosts I have on the machines. Not sure about Windows and Hyper-V.

I also just read somewhere that if you give a guest >1 vCPU VMware will wait until that many cores are idle before doing something on that guest to ensure that it gets both CPUs. I can definitely see how that would be a problem unless you've got cores to dedicate to a VM.

I am pretty sure that restriction disappeared in 4 but what they did do is work in core concurrency. So 2 vCPUs typically would be executing on the same socket which can cause contention if no 2 real cpus are available at the same time. There is a huge performance loss when trying to sync threads over multiple sockets. This is on top of the memory syncing that has to occur in the vCPUs themselves.

 

[bob4432]

again, thanks for the invalueable education. i will be ok w/ ram and disk i/o - been running 15k scsi for years and guess will finally actually get the real benefit of it 🙂 as far as the os's, i have them and would get the 2k8 via dreamspark - student setup - this is not for a biz but to get rid of some extra machines i have here - 1 is on 24/7 as the home server, but others are here just to gain knowledge of different os's. not sure how much i have to adhere to the license system since it is for student use and not a biz by any means.

i will move the vms to just 1 cpu/core as that is what the machines they are on currently and are not being pushed hard at all. the one machine that runs 24/7 keeps all the home backups on it from 4-6other machines, keeps video/music on it, runs ssl-apache, a ssl-ftp server and a teamspeak server. i would like to make this the main machine and then put a vm for my main/gaming rig on it, but that doesn't sound like it will happen, but i will still give a try and see how well the 3d acceleration works w/ it for gaming.

one question - say i have 8GB of ram and running 64bit as the main os - does the vm if set to 2GB always keep that amount away from the main os even if it is not used or does it just take what is needed?

 

[imagoon]

one question - say i have 8GB of ram and running 64bit as the main os - does the vm if set to 2GB always keep that amount away from the main os even if it is not used or does it just take what is needed?

Last I checked:
Hyper-V: no you use 2gig no matter what.
ESX(i): yes it only gets what it needs, even allows for over commit (assigning 12 gig with 8 gig of real memory.) It also uses "deduplication," as in if 2 memory segments are identical it will note that and release the duplicate, sharing it between multiple machines.
VMware on windows (workstation / server): I *think* it can clear up memory using the balloon drivers.

There is also some overhead for the VM so if you assign 2gig you might use 2.2 gig for example.

 

[Nothinman]

I meant you still need enough CPU to support the machines. Trying to run 8 vCores with and expected load of 80% per vCore on a dual physical core is heading towards a world of hurt no matter how many terabytes or RAM or terabits / sec of Disk I/O you throw at it.

That's obvious so I thought you meant VT extensions.

I am aware of the gaming. That is why I asked him what he is emulating. Hyper-V licensing prohibits the use of the Host machine for anything other than Hyper-V if you want to use the hardware license as a virtual license. So installing the DNS role on a Hyper-V machine with 1 2k8 guest would = 2 license needed where as removing DNS from the host would revert it to 1 license.

I haven't read the Hyper-V licensing but that seems sketchy. Unless you're talking about the free Hyper-V-only download MS has available which makes sense since you don't get full blown Windows Server for free.

VT extensions are night and day difference in performance on ESX(i) on all hosts I have on the machines. Not sure about Windows and Hyper-V.

I can't comment much on ESX because most of my experience is from the workstation side with VMware Workstation and Server. My machine here doesn't have VT and the only VM I have running performs just fine, disk I/O is the only bottleneck I can see.

been running 15k scsi for years and guess will finally actually get the real benefit of it

As much as I loved my Cheetahs way back when, they collect dust now. The Raptor I got with this machine years ago is more than comparable.

not sure how much i have to adhere to the license system since it is for student use and not a biz by any means.

You have to follow the licenses regardless. Your school might get you some really cheap or free licensing, but to be legal you still have to abide by them. And you might want to check those licenses because some of them become invalid once you're no longer affiliated with the school.

one question - say i have 8GB of ram and running 64bit as the main os - does the vm if set to 2GB always keep that amount away from the main os even if it is not used or does it just take what is needed?

VMware Server with 1 VM here and it's RSS is currently 161M so it should only use what it needs.

 

[imagoon]

I haven't read the Hyper-V licensing but that seems sketchy. Unless you're talking about the free Hyper-V-only download MS has available which makes sense since you don't get full blown Windows Server for free.

Nothing sketchy about it. Covered here:

http://www.microsoft.com/windowsserver2008/en/us/licensing-R2.aspx

Basically:

2k8 Standard = 1 host license for Hyper-V only + 1 guest 2k8
2k8 Enterprise = 1 host + 4 guest 2k8
2k8 Datacenter = licensed per cpu socket, unlimited 2k8 guests

Hyper-V only = must only have the hyper-V role installed. Adding anything else = you need to license the host itself. This includes shares etc.

 

[Nothinman]

Nothing sketchy about it. Covered here:

http://www.microsoft.com/windowsserver2008/en/us/licensing-R2.aspx

Basically:

2k8 Standard = 1 host license for Hyper-V only + 1 guest 2k8
2k8 Enterprise = 1 host + 4 guest 2k8
2k8 Datacenter = per cpu socket, unlimited 2k8 guests

Hyper-V only = must only have the hyper-V role installed. Adding anything else = you need to license the host itself. This includes shares etc.

Ah ok, I see what you mean now. But really, that makes sense because you don't want to put any other roles on the host if it's running VMs. And since they give you 1 guest license you can just put the other stuff in there so you don't really lose anything.

 

[bob4432]

Ah ok, I see what you mean now. But really, that makes sense because you don't want to put any other roles on the host if it's running VMs. And since they give you 1 guest license you can just put the other stuff in there so you don't really lose anything.

so you are saying that the best setup would be to install the main os, and only the vm software and do all the others via vms? will do if the gaming holds up.... 🙂

i am testing vm workstation atm and it seems to work ok for my very limited testing, will be installing it later on my main rig w/the e2160 on a current xp32bit install just to see how it works. i know it doesn't make much sense to put 32bit xp on 32bit xp but at least i could see how it fares gaming wise. or does win7 work better/more efficient as the vm os - 32bit?

thanks agian all.

i also need to change the vms network too - they are currently set as nat and not bridged...thanks for the mainline knowledge for those w/ it 😀

 

[Nothinman]

so you are saying that the best setup would be to install the main os, and only the vm software and do all the others via vms?

In general, yes. For a work environment, hell yes. For home, unless you've got a spare machine to dedicate to your VM host, don't worry about it.

i know it doesn't make much sense to put 32bit xp on 32bit xp but at least i could see how it fares gaming wise. or does win7 work better/more efficient as the vm os - 32bit?

I doubt it will matter much, although things like SuperFetch and Indexing may cause more I/O contention.

 

[imagoon]

so you are saying that the best setup would be to install the main os, and only the vm software and do all the others via vms? will do if the gaming holds up.... 🙂

i am testing vm workstation atm and it seems to work ok for my very limited testing, will be installing it later on my main rig w/the e2160 on a current xp32bit install just to see how it works. i know it doesn't make much sense to put 32bit xp on 32bit xp but at least i could see how it fares gaming wise. or does win7 work better/more efficient as the vm os - 32bit?

thanks agian all.

i also need to change the vms network too - they are currently set as nat and not bridged...thanks for the mainline knowledge for those w/ it 😀

We are talking about hyper-v licensing. MS will 'give' you a 2k8 install for hardware in the sense that the hardware install of the 2k8 does nothing but hyper-v when you buy a license. You then get 1 guest to use for everything else. So that same key installs the on hardware OS (2k8) and then lets you build 1 virtual 2k8. The net result is you get hyper-v but don't have to lose the license you paid for. Older licensing used to make you pay for 2 2k8 licenses.

 

[bob4432]

ms and their licensing, uuggghhh, it is a killer - wonder if one can get certified in that alone. my last build out for a person i did an office using ts/remote apps took about 6hrs on the phone w/ ms to get the right amount of the correct licenses - pita.

vmware workstation is looking good for me thus far - i can't find it on their site but is it limited to any amount of vms? i only need probably 5 or so and that would be enough for what i need + test.

also, since the "hdd" becomes basically an encapsulated folder on the main rig...is there any issue w/ corruption if the rest of the hardware is working fine? is there a higher chance of corruption in a vm vs a regular setup or is the encapsulation of the "hdd" pretty stable? i just don't want to lose a whole vm, especially what would be my important docs/photos due to some weird corruption issue and then no way of getting them back. is there a viewer i can see into the vmware file of the "hdd" on the main machine if needed?

 

[Nothinman]

ms and their licensing, uuggghhh, it is a killer - wonder if one can get certified in that alone.

https://partner.microsoft.com/40029101

Although, to be fair, there are sales certs for pretty much all of the big name companies. Our sales guys know more about Cisco licensing that I ever want to know.

vmware workstation is looking good for me thus far - i can't find it on their site but is it limited to any amount of vms? i only need probably 5 or so and that would be enough for what i need + test.

I don't think there's any limits on number of VMs, globally or running concurrently.

also, since the "hdd" becomes basically an encapsulated folder on the main rig...is there any issue w/ corruption if the rest of the hardware is working fine? is there a higher chance of corruption in a vm vs a regular setup or is the encapsulation of the "hdd" pretty stable? i just don't want to lose a whole vm, especially what would be my important docs/photos due to some weird corruption issue and then no way of getting them back. is there a viewer i can see into the vmware file of the "hdd" on the main machine if needed?

If the host hardware and drivers are fine, you should be fine too. It might not be a bad idea to put that machine on a UPS though, just in case.

VMware Server for Linux comes with vmware-mount that lets you mount images like any other filesystem. I have no idea if the Windows version has something similar or not.

 

[bob4432]

excellent - and yes, machine is on a ups 🙂 - have 2 on 1 already so i would just move this rig to the larger ups.

think i am going to go install it on the gaming machine, put win 7 on it and see how bfbc2 & coh in dx10 runs on the vm...wish me luck as i am only running a 4850 @ 1920x1200 😱

 

[Nothinman]

put win 7 on it and see how bfbc2 & coh in dx10 runs on the vm..

Looks like VMware Workstation 7 does DirectX 9, which is better than I thought, but I'd be surprised if they were even close to playable.