VM Performance SSD Pool vs Unassigned drives


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Hello

 

Wondering if anyone knows the answer before I reload my main rig the worse way.

 

With the new storage pools available, I'm curious are there any benefits (particularly VM performance) to having 2 M.2 SSDs in a storage pool vs the same drives in say a Raid 0 config from the motherboard and run them directly to the VM as unassigned drive?

 

I'm going to have a very simple setup starting with a single Windows 10 VM and a docker container running Plex.  Also would there be any difference in write performance from the Win 10 VM to the array cache drive (also SSD) with the two scenarios above?

 

Thanks

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After seeing @SpaceInvaderOne's April Fool's video, I saw he was able to assign independent drives, each to their own respective pool.  It made me wonder the same thing, do I leave VMs in unassigned disks?  Or do I create a pool with a single disk?  Are Pools Unraid's answer to "built-in" unassigned disks?  Without plugin needed this time?

 

I haven't tried USB on my Unraid to see if it will perform the same as Unassigned Disks though.

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Right, I think it might of been one his first videos talking about the new additional pools that got me thinking about this.

 

Now I find myself at a crossroad and I could go with either configuration if it would be better.  Hoping someone already knows.

Edited by EvAnA11
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The main difference that Pools provide over UD is the ability to participate in User Shares which UD devices cannot.   If this does not matter then it is up to you which you choose.   I believe that the expectation going forward is that pools will be chosen over UD except when there is a good reason to use UD so that they can take advantage of any enhancements in the future in pool support.

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7 hours ago, itimpi said:

The main difference that Pools provide over UD is the ability to participate in User Shares which UD devices cannot.  

And since you can also directly access them as disks instead of going through user shares, I don't see any advantage with UD for this.

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So I've got it running, but not finding the performance I was hoping for with x2 m.2 ssds in raid 0.  Maybe I'm asking too much of btrfs raid 0?  I'm also pretty new to all of Unraid.

 

Hopefully I've just got something set incorrectly because the transfer speeds don't seem right at all.

 

The Windows 10 VM vdisk is the sole thing currently running on the m.2 raid 0 storage pool but my transfer speeds are:

Copying to array cache (also an m.2 ssd) 155-190MBps

Copying from the array hdd to Win10 VM desktop is slower than usual around 130MBps (max is usually around 230MBps).

 

I'm also finding the VM gets super sluggish when transferring to the array but no seeing an obvious bottleneck.  Attaching some screenshots and the Win10 VM xml, hoping someone has an idea.  The VM is running Q35-5.1 and vDisk Bus is VirtIO

 

Thanks

copying to array cache.PNG

copying to array cache-cpu.PNG

win10vm-xml.txt

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