Kioxia has a new TLC-based SSD designed to bring up to 61.44TB to modern servers. With its PCIe Gen5 interface, the new Kioxia CD9P is designed for both capacity and performance. This is an update to the Kioxia CD8P-R 30.72TB PCIe Gen5 NVMe SSD we reviewed on STH.
Kioxia CD9P PCIe Gen5 NVMe SSD Era
Here is the overview slide from Kioxia. As a reminder, the Kioxia CM series is more of the enterprise drive with features like dual porting for high-availability arrays. The Kioxia CD series, like this CD9P is a drive designed for single node and scale-out style storage as it is a single-port design. They are just different design optimization points.
There are two versions of the CD9P. The CD9P-V is the mixed-use 3 DWPD drive that also features significantly better random 4K write performance. The CD9P-R is the read-optimized drive that is 1DPWD but comes in higher capacities.
The new PCIe Gen5 NVMe SSDs come in both EDSFF E3.S form factors (up to 30.72TB) and 2.5″ (up to 61.44TB.) Something that is also notable is that the mixed-use CD9P-V drives only scales to 12.8TB of capacity. That seems to indicate that Kioxia sees its high-capacity customers focus less on the 3 DWPD metric expecting less write pressure on the drive. That is similar to what we have seen with other SSD vendors and their capacity drives.
Final Words
High-capacity drives are always fun. The Kioxia CD9P is targeting not just the massive capacities, but also delivering higher performance at those high capacities. We recently covered the Kioxia CM9 PCIe Gen5 NVMe SSD launch where those drives are focused more on that enterprise feature set. Since we have seen the CD and CM series from Kioxia iterate for many generations over the years, it was only a matter of time until we got the CD9P series of drives.
“Something that is also notable is that the mixed-use CD9P-V drives only scales to 12.8TB of capacity. That seems to indicate that Kioxia sees its high-capacity customers focus less on the 3 DWPD metric expecting less write pressure on the drive.”
That second sentence doesn’t make much sense if you read it back. Are you trying to say that they aren’t concerned about capacity because they don’t expect as many writes to the drive? Then why would they be using the write-intensive drive vs. the read-intensive drive?
I’m guessing the point is they care more about durability than capacity. That is usually the reason 3DWPD drives have less capacity than their read-intensive counterparts (more raw flash overprovisioned, that kind of thing).
It’s notable how the 61 TB SSD has very different performance characteristics than the 15 TB SSD.
Comparing 4×15 TB drives to 1×61 TB drive, the random write 4 KiB performance is 1.800 KIOPS vs 100 KIOPS, a factor 18 difference.
This underlines the fact that these kind of drives are ideal only for a very specific use case, and cannot be recommend for general use cases.