Solved

Hyper-V dynamic RAM

Posted on 2014-09-08
3
560 Views
Last Modified: 2014-11-12
I have a 2012 R2 server hosting 2 Hyper-V servers that I have converted from VMWare. The host has 64GB, each guest had 16GB in VMWare but I was reading some best practices on Hyper-V and the dynamic RAM option was suggested as the way to go. The problem I am having is the RAM is not increasing as needed. When I log in and look at the Task Manager on the guest it shows 90% memory used and 16GB but the Hyper-V Manager shows around 4 or 6 GB is being allocated to that guest. It appears that something is not interfacing correctly. I updated the integration services seeing that was a common cause but it is still not functioning properly. For instance it is after hours and the RAM shows 97% used. There is no malware on the guest or host and all the processes are legit for a Terminal Server to be running. Any suggestions on what to do next?
0
Comment
Question by:PIMSupport
  • 2
3 Comments
 
LVL 56

Expert Comment

by:Cliff Galiher
ID: 40311135
Is there a reason you think it isn't working? Are you seeing a lot of paging or performance issues. Considering a VM with no added services will spin down to under a gig, seeing one run at 4 to 6 would make me think it is working just fine. More isn't being allocated because more isn't needed. Unused memory that is allocated is memory wasted. So you should expect to usage in the 90s percentage -wise. If it were pegged at 100 then you may have issues.
0
 

Author Comment

by:PIMSupport
ID: 40311190
The users are experiencing issues with performance that are not felt when I set the RAM to a static 16GB
0
 
LVL 56

Accepted Solution

by:
Cliff Galiher earned 500 total points
ID: 40311195
Well, you can set it back to 16 GB if you prefer. Or you can turn on performance counters on hyper-v and actual get some insight into what is going on.

Dynamic memory is beneficial in high-density environments, particularly those where VMs have mobility to handle host outages. It allows a VM to scale up for performance scale down to squeeze onto a new host in the event of a failure...or squeeze down ti make room for another incoming VM undr the same circumstances

For low density single host environments, there is little to no benefit.
0

Featured Post

How to run any project with ease

Manage projects of all sizes how you want. Great for personal to-do lists, project milestones, team priorities and launch plans.
- Combine task lists, docs, spreadsheets, and chat in one
- View and edit from mobile/offline
- Cut down on emails

Join & Write a Comment

From Coral's  "So You Want To Play With Computers" Series A bit of background first, so this story will make a little sense. One day, probably because he needed a good laugh, Finagle hooked me up with a church to upgrade/run their Media Booth.…
The recent Microsoft changes on update philosophy for Windows pre-10 and their impact on existing WSUS implementations.
In this Micro Tutorial viewers will learn how to use Windows Server Backup to create full image of their system. Tutorial shows how to install Windows Server Backup Feature on Windows 2012R2 and how to configure scheduled Bare Metal Recovery backup.…
In this Micro Tutorial viewers will learn how they can get their files copied out from their unbootable system without need to use recovery services. As an example non-bootable Windows 2012R2 installation is used which has boot problems.

760 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

19 Experts available now in Live!

Get 1:1 Help Now