Optimizing for lower energy consumption / repartitioning boot drive?

[HumblyNeil]

Hi all!

I've built a TrueNAS Scale machine running a Celeron G9505, on an Asus h410k and 32GB RAM. A pair of Ironwolf 4tb in a Mirrored array, I have 2 SSDs, one for the installation and one as a cache for the array. Currently, it runs at 29-32W irrespective of load.

I have noticed that I cannot spindown the drives when idle, and I think that's due to the fact that I have a couple of docker images running from the main storage.

Ideally, I am trying to lower the power consumption when the drives are not in use by spinning them down or utilizing some of the power-saving profiles available.

I had one thought to repartition the boot drive to allow the docker images to run from there. However, I'm not sure how or if that would be possible.

Can anyone advise me on this as a possible venture?

 

[NickF]

There is not an officially supported way to do what you are requesting.

 

[NugentS]

If you want to save a bit of power you can get rid of the cache - its almost certainly doing very little.
Whats you arc hit ratio? If thats > 90% then get rid of the L2Arc

 

[NickF]

At some point or another NVME namespace support should come. That would solve this type of issue. As in a single ssd for boot, l2arc and slog.

But unfortunately not something you can do today without getting into the CLI. Even then here’s no guarantee something won’t break.

For now the above is the best recommendation.

 

[sretalla]

Maybe sounds a little counter-intuitive at first, but stay with me...

Get an external SSD (I use Samsung T5/7, but whatever's cheap in your area is probably fine) and use that as your boot pool. (USB boot pool is fine if there's an SSD behind it rather than crappy thumb drive electronics)

Use your 2 internal SSDs as a mirrored pool to run your apps, system dataset (or put that on the boot pool) and hold anything that needs 24x7 disk access.

Use your HDDs to store backups of your apps and larger, less frequently accessed media.

Use the spindown script https://www.truenas.com/community/resources/hdd-spindown-timer.122/ to make sure your spinning drives don't spin more than needed (although, I note that I don't particularly recommend this course of action for the longevity of the drives, but if power consumption seems more important to you than wearing out your disks early, go ahead).