Recommendation for using Optane with TrueNAS Mini XL+?

[mikeschinkel]

Wow @NickF, thanks for all the help. MUCH appreciated.

@NicKF

You can install TrueNAS on a USB SSD (not a thumb drive).

Thanks for the links.

But not a SATA DOM? Reason?

@NicKF

In ZFS, the “Read Cache” is called L2 ARC. Generally, it is not really going to help much unless your system has >64GB of RAM… For that reason, I would say skip the L2 Arc unless you have at least 32GB of RAM.

Since your system is a small, low-power unit it doesn’t have alot of PCIE lanes to really get the most out of an L2ARC. FWIW, I don’t think you should bother.

So, let’s say I upgrade to 256Gb RAM once I get it. Then? Still don’t bother?

@NicKF

If you were actually storing your VMs on the NAS instead of Proxmox, with NFS or ISCSI, that’s when you would want to buy a SLOG.

Currently planning to keep VMs on my VM server, so I guess I don’t need write cache then, either?

@NicKF

If I were you, I would read up on the ZFS SPECIAL device, which I think may be more beneficial for you in the long run, given the constraints of the system. Also, buy as much RAM as you can afford.

Will do!

ZFS Metadata Special Device: Z - Wikis & How-to Guides - Level1Techs Forums

@NicKF

One Optane 118GB in the M.2 slot and the other can go in something like what was posted above, since you likely want a 10GBe card anyway. Though, you will be forced into SCALE with that specific card, as AFAIK there are no drivers for that chipset in CORE (FreeBSD)

Do I (really) need a 10GbE card when I have two (2) 10GbE ports on the motherboard?

@NicKF

If not, your best bet in that chassis would be to use SATA SSDs for a SPECIAL device in your pool. But obviously, while they aren’t nearly as fast as Optane, they are still faster than HDDs.

I will definitely check out that option. Thanks again!