Most effective use of a set of SSDs

[deslea]

I'm trying to work out the most effective way to put to use an existing set of 7x5TB SSDs. They're shucked Seagate OneTouch drives (2.5" Barracudas under the hood).

My existing TrueNAS Scale setup is as follows:

• Motherboard make and model: Proprietary - HP Z420
• CPU make and model: Intel(R) Xeon(R) CPU E5-1607 v2 @ 3.00GHz, average 5% utilisation
• RAM quantity: Right this minute, 32GB ECC, but I have come into some more ECC and will be opening it up on the weekend to bump it up to 96GB. (The HP mobo has eight slots).
• Hard drives, quantity, model numbers, and RAID configuration, including boot drives
  • Boot drive is a 100GB SSD, 96GB free
  • Pool 1 is spinning disks, mixed topology (I know, not ideal), 2x18TB and 3x8TB, total raw storage <60TB, set up as RAIDZ1, effective capacity 29TB, 13TB free (although I do have more data to go in). These are all connected to onboard SATA slots (the HP z420 has six AHCI slots).
  • I have a couple of LSI SAS controllers (flashed IT mode) so I will probably put in another set of 5x8TBs as another pool to take some extra data.
• Network cards: Just onboard gigabit. The key machines working with the data are also wired gigabit, although there are wireless clients in the mix.

My use case is basically just that of a very elaborate home lab/data hoarder - decades of photos, substantial media collection, etc, largely used in the home and with very limited remote use by extended family. (We have international careers, so there's potential for more intensive intermittent remote use, although right now we're just porting hard drive extracts). I keep cold backups onsite (made weekly-ish) and offsite (made about two-monthly, soon to be supplemented by AWS Glacier); the main purpose for the NAS is resiliency/error detection/self-healing/snapshots. I should say I live in a rather punishing tropical climate where everything has a shorter lifespan than typical even with the best of care, although I do monitor and manage temps in the systems pretty closely. But suffice it to say that any physical media calamity is generally more likely and more frequent than it was when I lived in a more temperate climate, and there is older data in the collection that has definitely been affected by bitrot, so I'm quite sensitive to those risks.

At present, five of the 5TB SSDs are in use locally (but only about 50% utilised) on another server for relatively intensive tasks and/or data desired fast-on-demand - Jellyfin, Photoprism, Paperless-ngx, local quick-access copies of VMs or large ISOs, Calibre, that sort of thing. These then back up nightly to TrueNAS. To a large extent, the nature of the data (with exceptions such as database files) is write once, read many times.

What I'm wondering is whether this is the best use of the SSDs, or whether they might be almost as fast, with convenience/reduced complexity/resiliency benefits as a trade-off, as a pool in the TrueNAS. (I do kind of like that these largely automated programs don't directly touch my TrueNAS data, although I think snapshots also give protection against a program going rogue, so I would be willing to let that advantage go).

I have read some threads and discussions about SSDs and speeds but to be honest a lot of it is at a deeper level of knowledge than I have; I can grasp the concepts but I am having trouble applying them to this scenario. I get that SSD performance in pools can be a bit of a mixed bag, that there is a wear and tear issue, and that the cost benefit is questionable if you were planning to buy some, but I can't glean whether the performance or wear and tear factors are so much worse than using them directly in a machine that you wouldn't consider using them in TrueNAS even if you already have them. So I would appreciate any wisdom people can share.

 

[sretalla]

7x5TB SSDs. They're shucked Seagate OneTouch drives (2.5" Barracudas under the hood).

I don't think those are what you think they are...

Those are HDDs, not SSDs.

And even worse, they look like they would be SMR:

CMR and SMR Hard Drives | Seagate US

See the list of recording technology utilized on our internal hard drives

www.seagate.com

If you absolutely must use them with ZFS (which I don't recommend):

Typically, those drives aren't made to spin all the time, so you might want to just make a RAIDZ2 pool out of them and set them to sleep (https://www.truenas.com/community/resources/hdd-spindown-timer.122/), using them for long-term (infrequently accessed) storage.

 

[deslea]

Oh, my goodness, you're right. The Seagate OneTouch range *is* SSD - but only up to 2TB, the higher sizes are HDDs (https://www.seagate.com/au/en/products/external-hard-drives/one-touch-external-drives/). I've been using these for years, having graduated up the storage sizes without a clue that there was a chance. They do perform noticeably faster than my 3.5" drives (particularly for robocopy backup scripts, so mostly comparing metadata), so I've never questioned it, but that could just be down to a better controller or something.

So in that case, and with the SMR issue in mind, it's sounding more and more like these should be used somewhere other than the NAS (in fact, probably staying in their current configuration). Many thanks!