Re: M2 NVME support

From: Andrea Venturoli <>
Date: Thu, 13 Apr 2023 12:56:21 UTC
On 4/13/23 13:25, wrote:

> We are in the process of buying new hardware for use with FreeBSD and 
> ZFS. We are planning whether to buy M2 NVME disks or just SATA SSD disks 
> (probably Samsung PM* ones). How is you experience with them?

I've never had any trouble with any SATA disks.
As for M.2, I only have a RAID-1 root pool on one box:
# nvmecontrol devlist
  nvme0: SPCC M.2 PCIe SSD
     nvme0ns1 (244198MB)
  nvme1: SPCC M.2 PCIe SSD
     nvme1ns1 (244198MB)
So far, so good, but it's quite new.

> Do you recommend one over the another?

M.2 should be a lot faster than SATA.
A good SATA RAID might be fast enough, however, depending on your needs.

In the low-end market I would go with M.2, provided you have two slots 
on the MB.

In the high-end, I'm not so sure...
SATA enterprise SSDs are available, M.2, AFAIK, not.
The new U.2 standard looks promising, but I'm not so sure it will catch 
on, while SATA will eventually disappear, but not any time soon.

> Or do they perhaps work better with some specific disk controller?.

You mean NVMe?
There is really no controller (as it is intended in SATA/SCSI/SAS/...), 
they just appear on the PCI bus.