Need help with NVME namespaces

Notice: Page may contain affiliate links for which we may earn a small commission through services like Amazon Affiliates or Skimlinks.

azev

Well-Known Member
Jan 18, 2013
768
251
63
Just now I read how single NVME can be split into multiple virtual drive by creating multiple namespaces.
Apparently doing this in VSAN shows significant improvement of performance and I want to give it a try.

I am looking at carving out multiple name spaces on my SM1725a nvme ssd, and so far I have not found any real step by step guide on the net.

If anyone here is familiar with the process; would you mind providing step by step guide on how to do this, either in Windows, Linux, or FreeBSD ??
 

Rand__

Well-Known Member
Mar 6, 2014
6,626
1,767
113
You have seen this?
VMware vSAN + NVMe namespace magic: Split 1 SSD into 24 devices for great storage performance

Luckily, because this is a standard NVMe feature, I didn’t need any special tools to configure the namespaces—I just used the built-in `esxcli nvme` commands to create them. The commands below show how a namespace can be created and attached to the controller.

Create:

`esxcli nvme device namespace create -A vmhba3 -c 1258291200 -p 0 -f 0 -m 0 -s 1258291200`

Attach:

`esxcli nvme device namespace attach -A vmhba3 -c 1 -n 1`

Once the namespaces were created, they showed up in the vSphere hosts as separate storage devices (not partitions). As far as the hosts knew, the namespaces were each separate individual physical storage devices. I was, in effect, tricking vSAN into thinking that I gave it multiple physical drives, when I knew that I was in fact only using a single physical drive.

Edit: Thats o/c for esxi, but since you said you wanted it for vSan that might be useful?
Not sure why you want to run in another OS
 

azev

Well-Known Member
Jan 18, 2013
768
251
63
@Rand_ that is the same publication I read that made me want to try carving out namespces. However I dont plan to use with VSAN instead possibly with my windows server or my FREENAS servers. Curently the Freenas have 4x 3.2tb NVME and I am curious if I can squeeze more performance by splitting each NVME to 4 equal sizes. This mean instead of 2 mirror vdev of 3.2tb, I can have 8 mirror vdev using the same hardware.