SSD Not Reporting Full Capacity

Hardware Hub Storage
1

I received my TrueNAS Mini XL+ from iX Systems yesterday and have been tinkering with it. (What I’m going to describe has already been sent to iX in a support ticket, but I’m impatient and so I’m here.)

I remember watching a video a while back where Wendell did something at the command line to make an SSD not show its full capacity (kinda like partitioning, but at a much lower level). The intent was to make the OS think it only had a portion of the capacity to work with and the SSD’s controller could move that reported capacity over the unused chips inside the SSD as the failure rate crept up - extending the life of a consumer SSD to make it last as long as an enterprise SSD.

I think (hope) that’s what iX did inside my Mini. Because I have a 480GB SSD (Micron 5400 MTFDDAK480TGA) that’s reporting its capacity as 14.91 GiB.

That SSH is meant to be used as the L2ARC for the Mini, but my needs do not outpace the ARC cache in RAM so I don’t need it. I want to use it along with the other SSD (another Micron 5400 MTFDDAK480TGA) to create a mirrored ZIL/SLOG vDev. But, I need the capacities to match for that to happen.

I guess what I’m asking after all of that is: Does anyone remember the video where Wendell showed this process? And more importantly how to undo it, so I can use all the space on the drive?

2

SSD Overprovisioning.

commands for truenas available here.

3

Thank you! That’s exactly what I needed!

4

I’d consider what ports/slots you have open in the NAS and see if you can find a lower latency/faster throughput SLOG device. The SLOG doesn’t need to be big, but low latency, high endurance and fairly high throughput are needed. The 64 GB Optane M.2s are a pretty good option if you can make room for 2xm.2.