PSA: Hyper-V Guests should be in High Performance Power Plan

I’m hoping this information will help others. Hyper-V guests can suffer performance degradation when not in the High Performance Windows Power Plan.

I came across this when a friend and I were trying to run a game server, Space Engineers I believe. We ran into some hard to troubleshoot performance issues. If it was not for the nature of computer games and the reliance on low latencies more so than most other home lab workloads I’m not sure I would have run into this problem.
After a few days of digging and trying different things we discovered that CPU parking was known to cause performance issues in this game and that parking was taking place on the system.
Some suggestions came up to try force the CPU not to park but I decided I’d play with the power settings after reading that this was a normal process carried out for power saving reasons.
Parking was introduced in Win7/Server2008R2.

Like magic everything became much better after changing the power plan. I now ensure all my Hyper-V guests have a group policy applied to them to set the power plan to High Performance. I anecdotally noticed a few other minor improvements with other systems that I didn’t originally attribute to being performance problems.

This was earlier in my HomeLab setup when I was running on an early Core i7 desktop computer running Server 2012 R2 with Hyper-V Role. I have not experimented with this on server running a Xeon processor but as it is primarily Windows Kernel function I imagine it is no different.
In light of this I have of course set my host to run to High Performance also.

There is some good discussion around power plan and performance in general here:

In saying all of this I can still imagine calculated scenario’s that one might might use power saving functions for their VMs. To achieve the obvious cost savings though a lot of effort would need to go into properly testing the applications that will be running on the VMs. Until you’ve done that the high performance plan is your safe bet.

The importance of backups

Everyone needs them, most don’t have them.

I see it so very often working in IT. A customer has a PC or laptop that stops working so they have the IT person look at it. Identify that the HDD has failed so the only option is data recovery or restore from backup. Data recovery costs normally start at $1000 but rarely does it stop there. Depending on the severity you should expect data recovery costs to be in the $2000 – $5000 mark and that is to attempt recovery there is no guraantee data will be recovered.

How could you have saved this headache? BACKUPS!
Keep everything in more than one place.

There is no excuse, for computers, there’s an external drive and windows backup is free. There are many other backup software solutions too.
Your flash drives and external drives aren’t safe either, they commonly fail. Keep the data on these devices on your PC also or again have another external drive that contains a copy of all this data.
Google Drive or Dropbox are suitable locations to store copies of your data. If you use Dropbox for example as your main file store ensure you have them backed up to your computer also. No online service is infallible so don’t rely on them solely to keep your data safe.

My personal experience with loosing data was this website. I was making changes to the database in the backend one day and accidentally deleted the wrong database. Lost almost everything.
I was lucky however that I had an old backup of the site minus a few posts so I was able to restore it to working order. I even managed to retrieve the content from the lost posts by visiting the Way Back Machine.
Now I’m sure to have scripted backups of all the data for the site and have it transferred to a computer elsewhere periodically.

Never underestimate the importance of backups. It will save you time, money and heartache. The only person who says they don’t need a backup is kidding themselves.

Protect Australia’s Freedom

One of the most important issues in Australia currently is upon us, stopping of the Trans Pacific Partnership agreement or more specifically the Intellectual Property component of this document. No explanation from me is required if you read the below.


A good bit of satire: