Help Me Decide

[minimos]

Hi,

 

I am looking at building an Unraid server to replace an existing W2k12 Essentials Server (AMD Turion II N54L with 10GB RAM) that acts as a domain controller for my home network.

 

The current server is holding up well for something that is nearly 7 years old, but as my needs have grown it beginning to creak and groan under the load (especially disk IO).  It is also not setup in the most ideal way (i.e it is installed bare metal with additional virtual machines running in Virtualbox), but it serves its purpose of running a DC, File and Backup Server, Pi Hole, Plex and a Grafana/InfluxDB VM for logging various IOT device attributes in my home.

 

I'm usually like to tinker rather than jump in and regret my decisions later, so I have setup a build using an old i7 3770k and ASRock Pro 4 motherboard with 16GB RAM and 1 old 2TB HD to get a feel of how Unraid would perform.

 

I've configured a new instance of Plex as a Docker container and enabled hardware transcoding through the CPU, I've also installed Win 10 as VM, URBackup and it doesn't really break a sweat, so CPU wise I appear to have enough compute, however as its an unlocked CPU edition it does not allow the use of IOMMU to pass-through a GTX 970 I have lying around.

 

What I'd like is some suggestions on Motherboard and CPU that would give me full IOMMU support, and some potential scope for the future without breaking the bank.  Ideally I'd also look at getting new kit as I plan on building this and letting it run for at least another 7 years.

 

Thanks in advance 

 

Minimos

 

 

[trurl]

I would argue that you haven't really tested Unraid until you have multiple disks plus parity 

[minimos]

Hi,

 

Thanks for the feedback.

 

Genuine question, would running more disks and having a parity drive really impact CPU to a high degree?  I know there will be some overhead, but I'm seeing 25 - 30% average consumption with 2 Plex streams Transcoding and a Windows 10 VM spun up.

 

I'm trying to understand potential costs, and I don't really want to spend on storage until I've bit the bullet and worked out the other components, especially as some drives will come across from my existing build

[trurl]

3 hours ago, minimos said:

would running more disks and having a parity drive really impact CPU to a high degree? 

No but having parity and at least 2 data disks will show you how Unraid storage behaves. Unraid IS NOT RAID; there is NO striping. Each disk assigned to a data slot is an independent filesystem. Because of this, Unraid is able to allow disks of mixed sizes.

 

Parity is updated realtime. When any data disk is written parity is calculated for that data and parity is also written. Reads from the array are at the speed of the single disk being read, but writes to the parity array are slower than single disk speed due to parity update.

 

[minimos]

Thanks for the explanation.

 

I'm assuming then that an SSD cache drive will help negate some of the performance hit for writes, and you configure to allow a VM to puts its virtual disk there?

[trurl]

Cache can be used to speed up writes to user shares, with files written to cache moved to the array according to schedule. Each user share has settings that control whether and how it uses cache. Cache is also often used as permanent storage for docker and VMs for better performance and so array disks can spin down.