Heya ya'll! Smooth brain here, just enough knowledge to get into trouble.

The short story - I'm getting ready to add new drives to a Plex and soon to be Immich server and go from a 4hdd raid z-1, to a 8hdd raid z-2.

Everything has been working great, but per Claude and Gemini some of my original settings should have been optimized differently (i.e. recordsize). At any rate, here is a pdf of what we all (they, lol) gathered and wanted to run it by the forum. Yes, my system has all the vdevs, specials, etc. and is probably overkill. My biggest questions are regarding the settings to be optimized before making the pool, and before adding any data.

Thanks for any help and remember, I am still just a n00b. Cheers ya'll!

Tower_ZFS_Settings_Reference_FINAL.pdf

Edited June 6Jun 6 by jlwitherell
grammar

1. What is the plan for the switch from RAIDZ1 to RAIDZ2? Is this going to be a brand new RAIDZ2 pool with all brand new disks or are you adding 4 new disks to an existing RAIDZ1 pool?

2. Why zfs pool and not just use the unraid array? Media playback certainly does not benefit from a raidz-pool at least not from a speed point of view.
   
   If the plan was to add 4 new disks to the existing raidz1 array, you cant convert it to raidz2, you can only add another raidz1 vdev which makes the pool 2 vdevs wide. To move to 1vdev of RAIDZ2 you will need to format the pool and start clean.

Edited June 5Jun 5 by MowMdown

Hi and thanks, I just moved all media off and was going to do a brand new raidz2 pool with the 8 drives. As far as not doing the standard unraid, I already have all the nvme's and everything - mirrored special read cach and even including an optane for the slog (lol), so was just going to do the full meal deal zfs. Yeah I know, way overkill, but correct me if I''m wrong, the zfs will still make the plex browser experience quite better through this zfs system. I will also be hosting immich, and a small chance down the road for other stuff running but not likely.

7 hours ago, jlwitherell said:

the zfs will still make the plex browser experience quite better through this zfs system.

Plex really only benefits putting the plex metadata (appdata) on an ssd.

Media playback is unaffected by disk I/O on an HDD. A single working drive can read anywhere between 80MB/s and 250MB/s (640Mbps to 2000Mbps) a typical 4K media file peaks at about 100Mbps or 12.5MB/s And those are 4K source copies. Most people I'd wager dont have full non-reencoded source copies media.

Where something like zfs does excel in is if youre video editing raw 4k/8k content over the network but even then you would want a full zfs setup using flash storage as even HDDs in a raidz pool would become a bottleneck for that workload.

The setup otherwise is fine, I mean there's nothing inherently wrong with what you're doing it just makes unraid an odd choice given that what I consider it's main selling point it's "array"

Thanks. Yeah, I'm aware of all that. I am actually just wondering about the specific drive settings when setting up the new pool. Did you look at the .pdf attached? Any input there?Thanks!

I did but I dont really think that level of micro-micro-management is necessary for a basic media server. (a raidz2 pool already being extremely overkill) Especially for data that is "wrote once and read many times"

I trust unraid/limetech to apply pretty sane defaults. I personally don't think you will gain any appreciable benefit and could very much make things a lot worse especially if you're new to zfs.

Edited June 5Jun 5 by MowMdown

My post specifically says that I know this is overkill and that I'm doing it anyway. This is how I'm setting up my server. I've already been using zfs. I'm sticking with it. My question was about the settings in the pdf. What would make anything a lot worse? It's ok to say that you don't know either.

38 minutes ago, jlwitherell said:

This is how I'm setting up my server.

It sounds like you know what you want already. Im not sure what further information I can provide based on what you've come up with in your write up.

Edited June 5Jun 5 by MowMdown

I will say, those settings are mostly subjective and should be tailored to the workload. For plex and immich, it wont really make a difference as that data is wrote once and read many times.

I understand that too, I specifically was asking claude and gemini about the best settings for my use case. The .pdf included here was the end result. They said they quadruple checked through every source (including forums).

What I was hoping to get was a ZFS expert to say, yeah, those settings look great, or no, don't do those specific settings because of x/y/z, to have someone, other than ai actually verify the settings look good.

Edited June 5Jun 5 by jlwitherell