SN550 - Why it uses 512B sector instead of 4096?

My WD Blue N550 1TB uses 512B sectors “out of the box”. So I often read modern drives are using 4096B sectors, but in special SSDs need it because its their internal size. If using 512B sectors this would also make double write cycles and so shorting the lifetime of the drive.

So, my smartctl output says:

Supported LBA Sizes (NSID 0x1)
Id Fmt Data Metadt Rel_Perf
0 + 512 0 2
1 - 4096 0 1

Can someone explain me what this means and/or/how is there a way to achive best settings for this drive? I’m using ext4, ntfs, fat32 filesystems and my working system is a Debian 9.

It there something like this also from WD? :


OK, it seems WD isn’t really interested to give detailed support to their products.
Also I don’t understand for what the SSD is delivered in the slower and lifetime shorting setting of 512b.

There is a way to change the firmware setting for (physically) sectorsize in Linux.

“# nvme id-ns -H /dev/nvmeXnY”


LBA Format 0 : Metadata Size: 0 bytes - Data Size: 512 bytes - Relative Performance: 0x2 Good (in use)
LBA Format 1 : Metadata Size: 0 bytes - Data Size: 4096 bytes - Relative Performance: 0x1 Better

so there is support for two different sizes :slight_smile:

“# nvme format --lbaf=NUMBER /dev/nvmeXnY”

will set the desired size where NUMBER is the value for LBA Format Code (look above)

That worked for me fine!

Of course the setting is OS indepent in further use of the SSD; the setting is stored in the device itself and keeps resist until you change it again.

!!! You will loose the complete content of the disk after changing the size !!!