Samsung 950 PRO M.2 NVM Express SSD

[bug77]

850-evo/MZ-75E250BW 97 000 IOPS qd32
950-pro/MZ-V5P256BW 270 000 IOPS (Thread 4) qd32

Yeah, because anything other than QD1 matters on the desktop. /s

[pal666]

Yeah, because anything other than QD1 matters on the desktop. /s

the only random read test in article was using aio, which would be pointless with qd1

[bug77]

the only random read test in article was using aio, which would be pointless with qd1

The original assertion was that, while the 950Pro looks much better on paper, it doesn't look so hot in the real world/benchmarks. My assertion was that specs are based on use cases that you're more likely to find on servers than on the desktop (large sequential access, high queue depth), hence the difference.

And about that QD1. With SATA you get 30-40MB/s. With NVMe you can get 50MB/s or a bit more. A mechanical HDD won't break the 1MB/s barrier. That's why you can feel the difference between a HDD and SSD, but not between a SATA and NVMe SSD. Of course NVMe is faster (and I expect it grow even faster, in time), but you won't be able to tell outside of benchmarks.

[pal666]

The original assertion was that, while the 950Pro looks much better on paper, it doesn't look so hot in the real world/benchmarks.

i talked about benchmark from this article. i agree that not all specs are sufficiently higher, i just don't understand how exactly it translates into these benchmark results. maybe they become cpu bound in the kernel, maybe there is something wrong with aio which is preventing it from using maximum queue depth... and this benchmark has sequential read test which also isn't sufficiently faster with nvme

[dweigert]

The best use case for something like this is not your boot/root drive, but for internal DB usage, especially if you have BLOBs in them. In addition, with the advent of using these with OpenFabric in a cluster, and data deduplication, you may be able to dispense with EMC or HDS arrays entirely for some applications (Ceph for instance). I'd love to see cards that you can plug multiple of these devices into, and use an PCI-e 3.x 16 lane slot to do real FAST I/O

[drSeehas]

... Lastly, I would like to know what is going on with the U.2 spec Intel brought forward as a replacement for SATA. Everyone seems to be ignoring it, which is fine if they want to boycott Intel... But we need something to replace SATA and SATA Express wasn't the answer, if not U.2... What?

U.2 is mainly used in the enterprise not consumer market.
There are U.2 OEM drives from Samsung too:

http://www.samsung.com/semiconductor/products/flash-storage/enterprise-ssd/MZQLV960HCHP

http://www.samsung.com/semiconductor/products/flash-storage/enterprise-ssd/MZQLV480HCGR

There is also a 1.92 TB version, but I haven't seen it yet.

[torsionbar28]

Lastly, I would like to know what is going on with the U.2 spec Intel brought forward as a replacement for SATA. Everyone seems to be ignoring it, which is fine if they want to boycott Intel... But we need something to replace SATA and SATA Express wasn't the answer, if not U.2... What?

U.2 isn't intended as a SATA replacement. It's intended as a SAS replacement. It implements NVMe using the SAS physical connector, but with the addition of a lot more pins. This enables OEM's to create enclosures housing large numbers of these drives, for use in the datacenter. U.2, like SAS, is also "dual port" for redundancy.

The consumer version is M.2 NVMe, which implements the same 4x PCIe lanes as U.2, but M.2 is not dual ported.