ESXi 5.1 and memory allocation

[kaze]

Hello all,

Just got FreeNAS installed on my ESXi 5.1 server. Right now it is just hosts FreeNAS and a Debian box. The box itself is an ASRock Vision3D that used to be an HTPC, but is now re-purposed as a home server. Here are the short specs:

i3 CPU
8GB memory (mobo only supports a max of 8GB)
SansDigital TR4UTBPN with 4x 3tb WD Red (12TB raw) in JBOD


My plan is:

1. Debian machine hosts small (7player) minecraft server, small ventrilo server, and uTorrent.
2. FreeNAS gets the SansDigital to itself and runs RaidZ1
3. The Debian box will host / download various open source software onto the FreeNAS box over an internal virtual network.
4. FreeNAS will also be a standard home CIFS filer / media streamer over the physical NIC.

The Debian box is a very slim build, with no GUI at all, and only the dependencies required for the three applications. I have Minecraft's Java application set to use no more than 1.75GB of memory, but I have never seen it use more than 30% of that, so the entire server typically uses <1GB of memory. The WD Reds haven't come in the mail yet so FreeNAS is just kinda sitting there doing nothing.

Right now memory is allocated like this:

FreeNAS - 5.5GB
Debian - 2GB

Since Debian usually uses such little RAM, I'd like to overcommit memory like this:

FreeNAS - 7 GB
Debian - 2GB

With the overcommitment I will be guaranteed more memory for FreeNAS most of the time, but occasionally run the risk of VMWare paging stuff on the local drive if the Debian performance suddenly exploded at the same time as FreeNAS (unlikely).

For this to work FreeNAS needs a balloon driver, which it looks like it does:

http://support.freenas.org/changeset/02a8b011b9ed4ae48c19219b9518b21cad3cbb56
"372 device virtio_balloon # VirtIO Memory Balloon device"

Thoughts?

 

[titan_rw]

You've read:

http://forums.freenas.org/threads/p...nas-in-production-as-a-virtual-machine.12484/

and,

http://forums.freenas.org/threads/a...ide-to-not-completely-losing-your-data.12714/ ?

If so, I assume you have a server grade motherboard to be sure that vt-d support will work with the HBA you plan to pass through to the freenas vm? Come to think of it, I don't think any i3's support vt-d.

Because otherwise, I wouldn't trust a virtualized setup with important data. If you're wanting to just test freenas, a 4 gig vm should be sufficient.

 

[kaze]

You are right... VT-d is not supported http://ark.intel.com/products/49020 :facepalm:

 

[titan_rw]

The stuff you run in a Debian VM, can it be run in FreeBSD? Because you can run freenas on bare metal, and then setup the plugins system and use the jail to install any freebsd compatible software. I'm pretty sure I saw somewhere that minecraft can run in a jail. I don't see why not as it's simply java. Ventrilo and utorrent, I don't know. I know my friends and I use teamspeak running on freebsd. Not sure about vent. There are other torrent clients that are available for use in the jail, if utorrent doesn't run in freebsd, and you're not married to it (utorrent).

Using the jail system instead of virtualization gets rid of the extra layer of complexity. And the jail is 'closer' to bare metal, as it's only os level isolation, instead of an entire hypervisor away from bare metal.

 

[kaze]

I'm going to upgrade the CPU to an i7-2640M. The mobo does support VT-d so I'm fine there. I'll also look into the jail system as well.

 

[kaze]

I ordered the compatible CPU today. I'm going to follow the recommended guide and do a separate flash drive, etc. I'll make sure that I have backups of all of the important stuff, and I'll let you guys know how it all works after a couple of months testing.