Why 64-bit Hypervisor Support Is a Big Deal

H

HardOCP News

[H] News
Joined
Dec 31, 1969
Messages
0
Citrix just released XenServer 6.5, their first 64-bit hypervisor – software that lets one machine create and run many “virtual” machines. So, what makes 64 the magic number? In the past, we’ve operated on 32-bit systems. But the proliferation of new devices that XenServer supports created the need for 64-bit support. For XenServer to use a device (say, a GPU), the device needs to be mapped into the input/output (I/O) space of XenServer’s management operating system, also known as “dom0.” Up until now, XenServer’s dom0 has been a 32-bit Linux operating system. That means all devices need to be mapped into just 4GB of system address space. That’s because 4GB is the most memory a 32-bit operating system can support. So a dom0 can only support a limited number of devices.

That’s a problem. In today’s servers, there are a lot of devices that need to get loaded into this 4GB address space. Storage controllers, network adaptors, management interfaces … and GPUs. Most systems today support at least two of our GRID boards. Some support as many as eight. That eats up a lot of space and memory. So with the 32-bit XenServer, eight was the limit for many servers. With the release of the 64-bit XenServer 6.5, Citrix has removed those memory and software limitations. A 64-bit dom0 OS allows us to load more stuff into a much larger I/O address space. That lets you scale. And scalability – the ability to pile more users into a system – is one of the biggest questions in virtualization.
 
I wasn't aware that a 32-bit hypervisor could run 64 bit machines. I guess ya learn something new everyday.

Doesn't Hyper-V already effectively do this?
 
It's about damn time. Not that I would move my VM's off of KVM, but it's nice to know that Xen is truly viable again.
 
Congratulations Xen... I guess?

I'm still sticking with ESXi.

Side note. VMWare dropped 32bit compatibility as even an option in 2009...
 
Zarathustra[H];1041371859 said:
Congratulations Xen... I guess?

I'm still sticking with ESXi.

Side note. VMWare dropped 32bit compatibility as even an option in 2009...
Click to expand...

No kidding. Did they not know what year it was?
 
I'd almost take Hyper-V over XenServer these days.

If you aren't a school district or some tiny municipality, pony it up and get vSphere.
 
Taco said:
I'd almost take Hyper-V over XenServer these days.

If you aren't a school district or some tiny municipality, pony it up and get vSphere.
Click to expand...

I'm not sure what would pick if I didn't qualify for the free license.

I have been very happy with ESXi (apart from a few annoyances, like how free licenses require the client to manage them, and this client is Windows only, requiring me to run a Virtualbox Windows guest on my desktop, so I can run the ESXi client, to manage my ESXI server. The lack of VMa in the free version, making using a UPS a bit of a pain ahs been a frustration as well)

It is - however - not lost on my that if you are a business and need to license it, ESXi isn't cheap.

Not sure what I would pick if i had to pay.
 
I have virtual hosts all over my lab with ESXi, Hyper-V, and KVM, and I use ESXi's free hypervisor and VirtualBox at home. I've never even considered using Xen since most of the backup software my users test is 64-bit only. We haven't had a 32-bit machine in at least three years. Heck, we've had requests from customers to test our products with HP-UX and AIX virtualization, but not XenServer. That should show how small their market share is.
 
Zarathustra[H];1041371955 said:
I'm not sure what would pick if I didn't qualify for the free license.

I have been very happy with ESXi (apart from a few annoyances, like how free licenses require the client to manage them, and this client is Windows only, requiring me to run a Virtualbox Windows guest on my desktop, so I can run the ESXi client, to manage my ESXI server. The lack of VMa in the free version, making using a UPS a bit of a pain ahs been a frustration as well)

It is - however - not lost on my that if you are a business and need to license it, ESXi isn't cheap.

Not sure what I would pick if i had to pay.
Click to expand...

Yeah, we have a total of 92 licenses in my lab, and three vCenter servers, all for software testing. Yeah, it's expensive. When I build a host, I make sure to max out the hardware so we get the most our of our licenses. It's more expensive to put licenses on an underpowered server than it is to go for a high end server.

I have three hosts in one software dev cluster with quad 8-core processors and 512GB of memory, and the 4 Enterprise Plus licenses and the vCenter license they take cost more than the systems. (The FC storage was repurposed from our products, so that didn't figure into the cost from my view of the project. That would have put it above the license costs.)
 
I haven't paid attention to Xen in forever. I just assumed they were on 64-bit. Well good for them.
 
I thought Citrix had given up on the Hypervisor market.
 
I know a lot of you are dissing xenserver, but last I checked pretty much ALL the big vm players use xen (not nec. xenserver)...

Great to see them going to 64-bit. I didn't run into any 32-bit dom0 limitations, but there are also TONS of performance improvements as well...
 
I've used XenServer a lot at home for learning purposes. The price was right, and I have yet to play with Hyper-V or VMWare.

Looking forward to trying the new version xD

Now.... do I still need to license crap to push out updates to each hypervisor? Cuz SSHing into each one to run updates was a HUGE pain in the rump.
 
cortexodus said:
I wasn't aware that a 32-bit hypervisor could run 64 bit machines. I guess ya learn something new everyday.

Doesn't Hyper-V already effectively do this?
Click to expand...

Pretty sure VMWare have had 64 on 32 host for some time now
 
Zarathustra[H];1041371955 said:
I'm not sure what would pick if I didn't qualify for the free license.

I have been very happy with ESXi (apart from a few annoyances, like how free licenses require the client to manage them, and this client is Windows only, requiring me to run a Virtualbox Windows guest on my desktop, so I can run the ESXi client, to manage my ESXI server. The lack of VMa in the free version, making using a UPS a bit of a pain ahs been a frustration as well)

It is - however - not lost on my that if you are a business and need to license it, ESXi isn't cheap.

Not sure what I would pick if i had to pay.
Click to expand...

Are you sure you can't just run a VM as your vCenter Server and License Server as VMWare's best practices suggest?
 
All I can say is:

Wow, they just got to this? No wonder I haven't heard of anyone using Xenserver since 2006....
 
cortexodus said:
I wasn't aware that a 32-bit hypervisor could run 64 bit machines. I guess ya learn something new everyday.

Doesn't Hyper-V already effectively do this?
Click to expand...

Sadly, I work with this all too often.

Zarathustra[H];1041371859 said:
Congratulations Xen... I guess?

I'm still sticking with ESXi.

Side note. VMWare dropped 32bit compatibility as even an option in 2009...
Click to expand...

I hadn't touched anything Citrix in years and then at my new'ish day job I had to start building 32bit stuff for Xen and couldn't believe they hadn't migrated to 64bit support. That's just lazy.

Zarathustra[H];1041371955 said:
I'm not sure what would pick if I didn't qualify for the free license.

I have been very happy with ESXi (apart from a few annoyances, like how free licenses require the client to manage them, and this client is Windows only, requiring me to run a Virtualbox Windows guest on my desktop, so I can run the ESXi client, to manage my ESXI server. The lack of VMa in the free version, making using a UPS a bit of a pain ahs been a frustration as well)

It is - however - not lost on my that if you are a business and need to license it, ESXi isn't cheap.

Not sure what I would pick if i had to pay.
Click to expand...

If you have to pay I think ESXi is the way to go. Both for performance and scalability reasons. Hyper-V is fine in smaller environments though so I guess the answer for me at least is ESXi in larger environments and Hyper-V for very small environments. Xen is something I would never touch if I didn't have to.

dgingeri said:
I have virtual hosts all over my lab with ESXi, Hyper-V, and KVM, and I use ESXi's free hypervisor and VirtualBox at home. I've never even considered using Xen since most of the backup software my users test is 64-bit only. We haven't had a 32-bit machine in at least three years. Heck, we've had requests from customers to test our products with HP-UX and AIX virtualization, but not XenServer. That should show how small their market share is.
Click to expand...

Unfortunately the environment I work with is huge and has a little bit of everything. We still deploy new 32bit Windows 2008 R2 virtual machines from time to time. And when we do it's always for the Citrix guys.

lcpiper said:
Are you sure you can't just run a VM as your vCenter Server and License Server as VMWare's best practices suggest?
Click to expand...

You can.

bds1904 said:
All I can say is:

Wow, they just got to this? No wonder I haven't heard of anyone using Xenserver since 2006....
Click to expand...

Sad isn't it?
 
Dan_D said:
Sadly, I work with this all too often.



I hadn't touched anything Citrix in years and then at my new'ish day job I had to start building 32bit stuff for Xen and couldn't believe they hadn't migrated to 64bit support. That's just lazy.



If you have to pay I think ESXi is the way to go. Both for performance and scalability reasons. Hyper-V is fine in smaller environments though so I guess the answer for me at least is ESXi in larger environments and Hyper-V for very small environments. Xen is something I would never touch if I didn't have to.



Unfortunately the environment I work with is huge and has a little bit of everything. We still deploy new 32bit Windows 2008 R2 virtual machines from time to time. And when we do it's always for the Citrix guys.



You can.



Sad isn't it?
Click to expand...

Curious how you got a SKU for 32bit Windows 2008 R2. :)
 
iamwhoiamtoday said:
I've used XenServer a lot at home for learning purposes. The price was right, and I have yet to play with Hyper-V or VMWare.

Looking forward to trying the new version xD

Now.... do I still need to license crap to push out updates to each hypervisor? Cuz SSHing into each one to run updates was a HUGE pain in the rump.
Click to expand...

Do you not know scripting?

Having to click things manually in a GUI for a large # of machines is actually much more PITA than scripting some ssh access.
 
Taco said:
I'd almost take Hyper-V over XenServer these days.

If you aren't a school district or some tiny municipality, pony it up and get vSphere.
Click to expand...

I work in an ESXi only environment, but Hyper-V is pfucking amazing these days. I think people still harken back to the 2008 r2 days of hyper-v. Its far beyond what i would even consider xenserver to be, which is a joke.
 
XenServer scales better than the other solutions when you consider licensing cost.

It's been rock solid in my experience using it for ~ 3-4 years.
 
4saken said:
Curious how you got a SKU for 32bit Windows 2008 R2. :)
Click to expand...

It might actually be the non-R2 version of it. We deploy it infrequently. I hadn't ever seen a 32bit version of Windows 2008 until I started working at this job.
 
4saken said:
I work in an ESXi only environment, but Hyper-V is pfucking amazing these days. I think people still harken back to the 2008 r2 days of hyper-v. Its far beyond what i would even consider xenserver to be, which is a joke.
Click to expand...

I work with a couple hundred customers. I know of 6 with HyperV installations. One is a school district, one is a very small local municipality, three are midsize businesses working to get off HyperV. One is a midsize business happy with HyperV(with the caveat that operational expenses to manage are higher, obviously licensing is much lower). But even he is looking to get off it due to it's lack of options around server automation.

Is HyperV as bad as it was in R2? Of course not. Is there still as big or bigger of a gap with it's competition? Hell yes. If you are a legit company or you are looking to scale into the present state of the data center, you are foolish to stick with MS.

As for XenServer. I'm in the local Citrix office often, even they give a wink and a nudge around not caring about XenServer. "Sell vSphere for the hypervisor and sell our stuff on top of it". If you are supporting and recommending XenServer it's time for some self evaluation.
 
You must log in or register to reply here.
Back
Top