I need more RAM, or not?

[IceBoosteR]

Hey guys,

I have upgraded my server (some build blog will come soon).
So I got my Xeon E3-1225v3 with 24GB of ECC memory. I have now much more storage in my server and want to use some VMs, as they can be created on SSD.
But with 40TB of storage + SSDs, I should not create VMs 4GB of RAM. Yeah well, I could ... but it is not recommended I think (FN has not enough RAM for serving data). Upgrading to the maximum of 32GB is uneconomical, so I may need a new plattform.
Or not? Can I run 1 VM or so?
At the moment, I have DDR3-1600 sticks, ECC of course. I could migrate to a new plattform with 8+ cores which is using DDR3 Ram, so I could reuse the modules. Upgraded to a new rig would lead into:
300 bucks mainboard
600 bucks CPU
750 bucks for DDR4 ECC memory (64GB)

Neither of this are good options. Maybe socket 2011-0/1 would be the way to go. With some fancy E5-2xx0v2 CPUs? What do you guys think. I am sure, the RAM is the showstopper here, because of the expensive prices.
I am currently often out of country, so I have not enough time to review all the options.
Maybe you guys have some ideas :)

Cheers,
Ice

 

[joeschmuck]

I do not understand what you are saying with respect to a VM with 4GB of RAM?

So you have 24GB or RAM and FreeNAS only needs 8GB which leaves 16GB RAM available for VMs. But if you are using iSCSI then you may be correct in the fact that you are short on RAM.

Maybe you should state what you really want to do. If you want to run a few VM's then I say go ahead and give it a try, see if the system works fine or not. If you start to see the "Swap Utilization" being used then you have hit your limit. Look at the use before hand, some users will have very minor usage like a few 100 KB. It's when you start seeing a GB or more being used then you know you ran out of RAM.

 

[IceBoosteR]

I do not understand what you are saying with respect to a VM with 4GB of RAM?

So you have 24GB or RAM and FreeNAS only needs 8GB which leaves 16GB RAM available for VMs. But if you are using iSCSI then you may be correct in the fact that you are short on RAM.

Maybe you should state what you really want to do. If you want to run a few VM's then I say go ahead and give it a try, see if the system works fine or not. If you start to see the "Swap Utilization" being used then you have hit your limit. Look at the use before hand, some users will have very minor usage like a few 100 KB. It's when you start seeing a GB or more being used then you know you ran out of RAM.

@joeschmuck I am so sorry. Thats happening when you write forum threads late in the night...
So what I wanted to say. Right now I have everything running on ESXi hosts connected via iSCSI. But this doesn't matter. I would like to run sone bhyve-baded VMs (ubuntu, windows) on my FreeNAS server, and would like to give them 4GB of memory. With that said, it may be a conflict with the ressources FreeNAS wants to use for ARC or internals, but are used instead by the VMs.

So following your words, I should give it try, yes?

Thanks! :)

 

[danb35]

Well, it wouldn't hurt to try.

 

[joeschmuck]

Thats happening when you write forum threads late in the night...

Trust me, I can relate.

Right now I have everything running on ESXi hosts connected via iSCSI.

I'm probably not following your correctly. Are you saying that your server is running ESXi and FreeNAS is presently a VM on that server? If that is what you are saying then my recommendation is to use ESXi for all your VMs, do not use FreeNAS. This is my personal preference and how I have my system configured because ESXi is strictly built to run VMs whilst FreeBSD bhyve is a fairly new product.

Now if your plan is to run FreeNAS on bare metal then that changes things and I'd say give it a shot, or if you are just playing around with bhyve then that is fine too. Just look at the Swap Utilization and if it starts to get hit then you know you are out of RAM.

 

[IceBoosteR]

Trust me, I can relate.


I'm probably not following your correctly. Are you saying that your server is running ESXi and FreeNAS is presently a VM on that server? If that is what you are saying then my recommendation is to use ESXi for all your VMs, do not use FreeNAS. This is my personal preference and how I have my system configured because ESXi is strictly built to run VMs whilst FreeBSD bhyve is a fairly new product.

Now if your plan is to run FreeNAS on bare metal then that changes things and I'd say give it a shot, or if you are just playing around with bhyve then that is fine too. Just look at the Swap Utilization and if it starts to get hit then you know you are out of RAM.

Hi,
I think things are getting mixed up now.
I have two HP servers, which are running ESXi and are connecting to FreeNAS as a storage plattform. FreeNAS is running bare metal, no VM somewhere. But I want to use bhyve for one or two VMs (the important ones) so I don't need to spin up my physical hosts again and again :)

So maybe trying (like @danb35 said) is the way to go .

 

[joeschmuck]

Okay, I'm clear now. Yes, I'd give it a shot. The worst you can do is slow the crap out of FreeNAS. Pay attention also to your iSCSI performance as well. And try to give your VMs only the RAM they need, so if you run Windoze then can you only use 1GB or 2GB RAM? Ubuntu is not very needy either.

 

[IceBoosteR]

Okay, I'm clear now. Yes, I'd give it a shot. The worst you can do is slow the crap out of FreeNAS. Pay attention also to your iSCSI performance as well. And try to give your VMs only the RAM they need, so if you run Windoze then can you only use 1GB or 2GB RAM? Ubuntu is not very needy either.

Ok I will try.
1GB is way to less, maybe 2 at a bare minimum. Does FreeNAS allocate the VM memory 100% or just the amount the VM is needed? This could help for planning capacity.

 

[joeschmuck]

Does FreeNAS allocate the VM memory 100% or just the amount the VM is needed?

I have no idea, I have not used bhyve at all. I would hope that you can allocate a certain amount of RAM.