Actually it depends on firmware/model. I used to have two PM1725 and one was supporting namespaces. It might be that standart worked and Oracle did not, or other way. I got another 6.4T drive, not Oracle, and it doesn't support NSLooks like the Intel 4510 support namespaces as well.
Which Intel® Data Center Drives Support Multiple Namespaces?
Describes support of multiple namespaces in Data Center drives.www.intel.com
my Oracle F320 (Samsung 1725a) does not support them:
the key indicator seems to be this :
# nvme id-ctrl /dev/nvme1 -H
oncs : 0x6
[5:5] : 0 Reservations Not Supported
[4:4] : 0 Save and Select Not Supported
[3:3] : 0 Write Zeroes Not Supported
[2:2] : 0x1 Data Set Management Supported
[1:1] : 0x1 Write Uncorrectable Supported
[0:0] : 0 Compare Not Supported
I will use two of those drive to split them in cache tiers, to create 4 Disk groups in vSAN.
List of NVMe drives that support namespaces or other ways to divide one up
- Thread starter billc.cn
- Start date
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I recently discovered namespaces and and got pretty intrigued. There are interesting use cases, however vSAN performance improvement is not one of them.
The vSAN performance uplift is more proof of the poor utilization of single drives by vSAN that is "fixed" by tricking vSAN into thinking you have more disks via namespaces.
It's possible that vSAN was developed with SATA/SAS drives in mind, and relative random IOPS figures, and they didn't think adding more parallelization over single drive would help.
The vSAN performance uplift is more proof of the poor utilization of single drives by vSAN that is "fixed" by tricking vSAN into thinking you have more disks via namespaces.
It's possible that vSAN was developed with SATA/SAS drives in mind, and relative random IOPS figures, and they didn't think adding more parallelization over single drive would help.
I have to clarify my original post is not about performance but (working around) the vSAN requirement that each disk group needs a dedicated cache disk.
With vSAN (OSA) in an all-flash configuration, any single disk failure brings down an entire disk group, so I opted to create one disk group for each capacity disk. We can have up to 20 SAS/SATA capacity disks per server, and it's not practical to have that many NVME caching disks. Having an unnecessarily large cache disk also significantly increases the RAM usage of vSAN (unless they start making 128GB or smaller enterprise SSDs again). Hence using namespaces to allow one drive to serve as the cache for multiple disk groups. In my risk assessment, there are other single point of failures like the SAS controller and vSAN RAID can handle all local disks going offline any way.
