Hyper-V Program Manager
Have you started looking at dynamic memory in Windows Server 2008 R2 SP1?
If you have not – why??
I have been using dynamic memory on my home server infrastructure since January at the begining of this year, and have become completely addicted to it. Recently I decided to setup a Remote Desktop Gateway server so that I could easily and securely connect to my various home server systems when I was at work.
I have notice that it has been sporadically dropping connections (and then immediately reconnecting). There are a number of things that could be causing this (and top of the list would probably be that I am using pre-release software for pretty much everything) but I decided that the first thing I would try would be to give the server more memory.
So while I was at work – I connected to my Hyper-V server (through the Remote Desktop Gateway virtual machine), opened the virtual machine settings for the Remote Desktop Gateway virtual machine, and changed the memory buffer setting from 20% to 30%.
Instantly my Remote Desktop Gateway server received more memory – while I was connected to other servers through the gateway – all with no downtime. Neat!
Now to wait and see if this fixes the dropped connection issue.
Not to be Debbie Downer, but I'll wait for others to use Dynamic Memory in the real work with this in the RTM SP1 for a while until I start using it.
Cowardly (or shrewdly?) Yours,
Any hints on how close SP1 is to RTM?
I will use it on our Dev hyper-V hosts as soon as it comes out, but not in RC or Beta.
"If you have not – why??"
Because our remote desktop gateway server might start sporadically dropping connections. I think you answered your own question ;)
If I update a 2k8 R2 server with SP1 beta, should I be able of aplying SP1 RTM?
Furthermore, any ideas when a Hot-Add memory feature will be possible with Hyper-V - will this be included in SP1? Cheers :)
@Ian: Dynamic Memory uses hot-add memory to add memory to running VMs.
True, but I hope you are at least able to setup a test server on the side to be looking at this - and ensure that it works with your environment.
Ian Burrowes -
Sorry, I cannot and will not discuss release dates.
Rik Hemsley -
Good one. Unfortunately (or fortunately depending on your perspective) this change did not solve my problem - so I need to keep digging in to figure out why it is dropping the connection occaisonally.
Yes, you are correct.
Re: Hot Add Memory
So let's say I have a customer that has paid for a Windows Web Server R2 VM that has 2 CPUs and 2GB RAM, and this customer expects that the load on his website will increase in one week when he does a marketing campaign. So he wants to pay to increase the RAM on his VM to 8GB, without suffering any downtime because his global site is accessed 24/7. He might pay for the extra memory for one month and then go back to 2GB.
Can I use a Hot-Add Memory like feature to upgrade his VM from 2GB to 8GB without turning off the VM?
I see this as different from Dynamic Memory, because I want to limit customers to what memory they have paid for, and if they are all over provisioned from day one I can't up-sell them more capacity. Also, VMs will behave differently depending on how much memory they have, for instance SQL Server often eats up as much as is available, so if I over provision all servers to 16GB just in case I need to use that level in the future I will quickly run into capacity issues.
Please feel free to explain if I am misunderstanding the dynamic memory feature. I think it is great for internal VMs, but there still needs to be a Hot-Add feature for memory and also CPUs for that matter.
Re: Release dates
No problems Ben, I didn't expect you to reveal anything just thought I would try... hehe. Won't ask again :)
Today you can set the startup and the maximum memory for a virtual machine - and it will then move between those values as needed - however you cannot change the maximum memory at runtime (which is what you want to do here). This has been asked for a number of times now - but it is unlikely to change for this release (sorry).