SSD in Array

[Nelson]

Im wondering is there any support for SSD in Array for unraid? Im thinking of simple consumer grade SSD like a samsung 850/860/870 or crucial MX series, etc.

 

I remember it was said that while unsupported, people were saying that it had little to no problem with ssd in their array, they just need to disable trim. But if you did that it would have an impact on write speed overtime.

 

For my use case, I am mostly using this as a server for storage, a lot of 'write' once, and then read that file every so often. so say If i take a ssd and keep writing to it until its full or close to full, how much would the read and write performance be impacted? I would to keep the 2 drive parity from unraid as well. would that have an impact on my files and read/write speed as well?

[Squid]

Read performance won't be affected

 

Write performance will be due to:

• No trim support when in the array
• Array writes are always limited by the slowest drive (of either parity or data if in Read/Modify/Write, or all the other drives when in Reconstruct Write)

The "unsupported" was due to the questions regarding background garbage collection taking place invalidating parity which has turned out to not be a real issue.

[Nelson]

4 hours ago, Squid said:

Read performance won't be affected

 

Write performance will be due to:

• No trim support when in the array
• Array writes are always limited by the slowest drive (of either parity or data if in Read/Modify/Write, or all the other drives when in Reconstruct Write)

The "unsupported" was due to the questions regarding background garbage collection taking place invalidating parity which has turned out to not be a real issue.

So if i turn off trim, will i still be able to get the 2 drive parity? and how much write performance will be lost? is it like 10% or 50%

[Squid]

Writes are always limited by the speed of the slowest drive in the array (in reconstruct mode), or the slowest parity drive (and data drive being written to) in read/modify/write

 

The latter mode (Unraid default) is ~4x slower than the former, but only the drives involved need to be spun up while in reconstruct mode all drives must be spinning.

 

IE: if you've got spinners as the parity drives you will not see any write performance increases at all.

[Nelson]

9 hours ago, Squid said:

Writes are always limited by the speed of the slowest drive in the array (in reconstruct mode), or the slowest parity drive (and data drive being written to) in read/modify/write

 

The latter mode (Unraid default) is ~4x slower than the former, but only the drives involved need to be spun up while in reconstruct mode all drives must be spinning.

 

IE: if you've got spinners as the parity drives you will not see any write performance increases at all.

I'm thinking of changing the parity drives to sata SSD as well, so probably not that much difference then? I originally thought about raid 10 with 3.5 drives but 4-6 3.5 already creates quite a bit of noise.

 

I am thinking of making a diy case that can fit 30 drives, but how much would acoustic foam inside case help? And how much would it affect thermals and airflow?