Questions around vm's and networking

[Mortalic]

I'm new to unraid. Let's get that out of the way.

I've built a decent system, I've got a docker container running minecraft pretty well.

 

Question 1, how do I build a vm with no network attached?

 

Question 2, is there something I can do to make windows vm's more responsive?

 

The two windows vm's I've built seem to be spotty on their responsiveness.  I'm not doing any pass through on them and they are pretty average configuration, 4gb ram, 4 cpus, 60gb disk etc...  The server is a pretty beefy 12 core r9 with lots of ram and disk including ssd in the cache pool, so it seems like two vm's not doing anything yet should be a bit more responsive.  Most of the posts I find are all about cpu and cpu passthrough and for these I don't need/want any of that.

 

Question 3, Regarding docker containers and performance, I've got a small minecraft server running in MineOs-node and it seems to run well, but I do notice one cpu core stays pegged at 100% for extended periods of time.  Is this normal? Or do I need to do something to make docker more efficient?

 

Thanks in advance

 

ryzen r9 12 core

msi mpg x570 gaming plus (latest bios available)

64 gb ram

Array parity check completed.

3 hdd,

1 ssd (cache pool)

 

[IrishFavor]

Few questions that may help get answers for you.

 

• When you say performance issues are you referring to network slowness (ie. transferring stuff to the VM over the network, browsing the internet) or slowness within the VM where opening files and directories and applications stored on the VM are slow? or a bit of both?
  • Another question related to the above are you running your VM from your cache pool or from your storage array?
• Second about building a VM with no network attached if i remember correctly you will configure the IP address and network settings in the host os on the VM, Perhaps someone else can confirm this as my service is down for the moment and im having some issues with booting to unraid.

[PeteAsking]

Make sure you install the guest vm additions or vms will be slowish. Ie, disks shouldn’t be set to virtio and not ide or something if you have done it correctly. 

[Mortalic]

16 hours ago, IrishFavor said:

Few questions that may help get answers for you.

 

• When you say performance issues are you referring to network slowness (ie. transferring stuff to the VM over the network, browsing the internet) or slowness within the VM where opening files and directories and applications stored on the VM are slow? or a bit of both?
  • Another question related to the above are you running your VM from your cache pool or from your storage array?
• Second about building a VM with no network attached if i remember correctly you will configure the IP address and network settings in the host os on the VM, Perhaps someone else can confirm this as my service is down for the moment and im having some issues with booting to unraid.

Man I appreciate the help!

Not sure how much this matters but I selected SATA for os iso and virtio iso. 

First example, I installed a server 2016 vm and after first boot I went to install the guest additions.  It sat about 50% on these for probably a solid 7-10 minutes.  It did finish though.

Also, on this same vm I clicked start as I wanted to run 7 zip (I installed it first) and the start button didn't come up for a solid 30 seconds.

I just installed a windows 10 vm though and it seems a bit more responsive.  Copying to/from seems ok, definitely not getting the gigabit switch of 125MB/sec though.

 

Regarding running the VM on the cache pool, I didn't specify a disk or anything, so I'm not exactly sure what determines if it's running on the cache pool or not.

In order to try and answer your question, I looked at the disk location for the vm and it seems it points at the domains share.  When I look at the domains share it has all disks included but use cache is set to no.  So I think that means the vm isn't using cache.  Should I change the default vm share to a different one and set it to use cache?

 

For you last point, if I wait until the vm is booted it reaches out to windows update and begins it's update process pretty quickly.  I know I can disable it in the vm but usually it's already too late.  Which is why on my hyper-v server I don't even add a network initially.    This one isn't a huge deal, more an irritation.  Just would be nice to not have to deal with that when I'm just going to play the vm away later.

[Mortalic]

12 hours ago, PeteAsking said:

Make sure you install the guest vm additions or vms will be slowish. Ie, disks shouldn’t be set to virtio and not ide or something if you have done it correctly. 

Yes definitely doing this.  Using SATA and installing the guest additions as soon as it boots.

[PeteAsking]

If you are not using an SSD then likely VM's will be slow. Try using an SSD if you are not.

[Mortalic]

Ok, is there anyway to move the vm to a new share?  Do I just power it off, copy it in bash then change the pointers in unraid UI? Or is there an easier way?

[PeteAsking]

I normally just login via ssh and use the mv command to move the disk (vm must be off) then edit the xml to point to the correct location for the disk file. It doesnt take long. 

[Mortalic]

Ok, I created a new share called vmdisks, and set the "Use Cache" value to yes

 

I then moved both vm's to that and powered them on.

It doesn't seem like it's really all that better.  I'll play around with it and see.  One example, I installed 7-zip copied a small (3MB) archive and extracted it.  The opening process seemed to hang for several minutes.

Watching cpu usage during this time there was minimal activity. 

It seems the system was temporarily hung and this might be the heart of the problem.  I say that because my daughter was playing on the minecraft container and it also hung.

 

I think I may have a larger issue that I only thought was the VM's because that's all I was really using.  Any idea how to troubleshoot?  It seems to be happening during a write operation. So I'm wondering if one of my disks might be acting up.  The array shows all green and parity is complete though...

Edited July 22, 2020 by Mortalic
grammer

[PeteAsking]

It would be strange if it happened after moving the vm to the cache as a write operation to the cache is like writing to a single disk, outside of the array or anything so not sure how that could hang the system, or how it could still happen when before it was part of the array and now its happening when not part of the array if you see what I mean.

[Mortalic]

28 minutes ago, PeteAsking said:

It would be strange if it happened after moving the vm to the cache as a write operation to the cache is like writing to a single disk, outside of the array or anything so not sure how that could hang the system, or how it could still happen when before it was part of the array and now its happening when not part of the array if you see what I mean.

Yes I do see what you mean...

One of my disks is a very old drive that I pulled out of a nas.  I excluded it from the vmdisks share and the minecraft share as well.  Both seem to be running fine now. 

Could the drive being flakey (as opposed to actually throwing SMART errors) be causing unraid to just behave erratically?

 

I've got some new disks that should get here on Friday, so I'll remove it from the array entirely then.

[PeteAsking]

11 minutes ago, Mortalic said:

Yes I do see what you mean...

One of my disks is a very old drive that I pulled out of a nas.  I excluded it from the vmdisks share and the minecraft share as well.  Both seem to be running fine now. 

Could the drive being flakey (as opposed to actually throwing SMART errors) be causing unraid to just behave erratically?

 

I've got some new disks that should get here on Friday, so I'll remove it from the array entirely then.

I guess you have proved that it is possible.

[Mortalic]

3 minutes ago, PeteAsking said:

I guess you have proved that it is possible.

Have I though? lol More like wild speculation.

[PeteAsking]

Sounds plausible to me.

 

[Mortalic]

1 minute ago, PeteAsking said:

Sounds plausible to me.

 

Fair enough, I'm rolling with this idea unless the weird pausing behavior comes back.

I want you all to know, I really appreciate the assistance.

[itimpi]

4 hours ago, Mortalic said:

Ok, I created a new share called vmdisks, and set the "Use Cache" value to yes

If a share is set to Use Cache=Yes this means initially create the file on the cache, but later move it to the array.    You probably want Use Cache=prefer.   The help built into the GUI gives more information on how the various settings for a use Cache work, and how they affect the mover application

[Mortalic]

58 minutes ago, itimpi said:

If a share is set to Use Cache=Yes this means initially create the file on the cache, but later move it to the array.    You probably want Use Cache=prefer.   The help built into the GUI gives more information on how the various settings for a use Cache work, and how they affect the mover app;ovation.

Interesting, I'll read up on that. Thank you.