A SSD based Unraid NAS?

It seems they've designed an Unraid oriented product that is not fully compatible with the Unraid array due to the SSD TRIM issue that can/will invalidate parity.

 

 

Edited August 31, 20232 yr by Lolight

3 hours ago, Lolight said:

due to the SSD TRIM issue that can/will invalidate parity.

If they are using SSDs in the array trim won't work, but parity will remain valid.

1 hour ago, JorgeB said:

If they are using SSDs in the array trim won't work, but parity will remain valid.

Well, they must use SSDs in the array to have parity protection.

 

In that case TRIM will be disabled in Unraid, but it's not the only garbage collection mechanism implemented by SSDs.

It seems every SSD manufacturer has their own proprietary algorithm written internally into the controller, which functions independently of the OS.

And since parity calculation depends on knowing the exact location and value of every single bit on every drive, given enough time, SSDs in the array will inevitably corrupt parity.

Edited August 31, 20232 yr by Lolight

For several years now I've tested many different SSDs, and there are many users with SSD based arrays, and there's never been reports of any sync issues, exception is an old Kingston SV300 model which caused a couple of sync errors after a power cycle, but that was a specific device problem and unrelated to trim/garbage collection.

1 hour ago, Lolight said:

Well, they must use SSDs in the array to have parity protection.

Could be the trick of 1 random USB Flashdrive to have something in the array and all the other drives in Pool(s) with BTRFS/ZFS Raid.

 

However, it's a decision that is OK to do for a end user understanding the OS and the limitations & requirements of doing that. Doing that out of the box on that kind of system seems risky.

OR

They except that by then, the Array requirement will be lifted as already hinted at. (6.13 ?)

 

As for your question on the other thread about Limetech information / involvement, they could plan for using the OEM option, maybe ?

 

But from the video it does not look super serious so everything is possible.

3 hours ago, JorgeB said:

For several years now I've tested many different SSDs, and there are many users with SSD based arrays, and there's never been reports of any sync issues,

That's something that I was totally unaware of.

I was under impression that Unraid devs still don't recommend installing SSDs in parity protected arrays.

As per Unraid docs:

 

"SSD support in the array is experimental. Some SSDs may not be ideal for use in the array due to how TRIM/Discard may be implemented. Using SSDs as data/parity devices may have unexpected/undesirable results".

 

https://docs.unraid.net/unraid-os/manual/storage-management/

3 hours ago, ChatNoir said:

Could be the trick of 1 random USB Flashdrive to have something in the array and all the other drives in Pool(s) with BTRFS/ZFS Raid.

 

However, it's a decision that is OK to do for a end user understanding the OS and the limitations & requirements of doing that. Doing that out of the box on that kind of system seems risky.

OR

They except that by then, the Array requirement will be lifted as already hinted at. (6.13 ?)

 

As for your question on the other thread about Limetech information / involvement, they could plan for using the OEM option, maybe ?

 

But from the video it does not look super serious so everything is possible.

@SpencerJ has confirmed that their system will come with the Basic Unraid license.

Guess will have to wait on setup arrangement details until Robbie at NASCompares receives a test unit or Limetech releases additional info.