Seagate working on a spinning rust drive that is NVMe connected

[Izerous]

I'm not really sure I understand the benefit of this unless SATA is bottlenecking the HDDs,

Sata III = 600MB/s (6Gb/s)
First Gen Dual Actuator drives are capable of sustained ~520MB/s
so yes SATA is very close to being the bottle neck.

"Performance Characteristics: SAS 12Gb/s vs. SATA 6Gb/s. The first-generation MACH.2 product will come very close to saturating the SATA 6Gb/s interface (600MB/s throughput). As stated above, the drive will have a 520MB/s sustained data rate (SDR) and next-generation drives will perform even better. Hence, the design decision was made to enable ecosystem and storage architectures to readily deploy next-generation MACH.2 drives without changing interface protocols."

https://www.seagate.com/files/www-content/solutions/mach-2-multi-actuator-hard-drive/files/tp714-dot-2-2006us-mach-2-technology-paper.pdf

This is all server based stuff for now it will be years before we see this trickle down either way. Basically these new drives are already SAS only because SATA isn't close to being enough for them. A quad-actuator drive would almost saturate a SAS connection

 

[Entz]

NVMe is a much lighter / lower latency protocol that doesn't have all the baggage AHCI/SAS has. Once you go large cache/multi-actuator the single command queue (32 commands max/254 for SAS) and single interrupt design of ACHI starts to bite you in the arse. NVMe doesn't have those restrictions (65K queues at 65k command each, 2048 interrupts, hardware offload etc).

This also gets super simple NVMeOF and easier consistent backplane designs

 

[Shadowarez]

we would need new design for raid cards in future instead of 2 sas ports with break out cables we would need have something with new connector by time i get this nas up and running it will be maybe 2 years in service before change over.

 

[Entz]

Those already exist, this is nothing really new to enterprise. SFF-8653 / SFF-8654 already carries PCIe and SAS. The U.3 spec exists to combine everything into a single drive connector in a nice clean way vs U.2/SATA express -- fewer pins, better management.

There have been hybrid controller available for a while (2017+) that that combine SATA/SAS and NVMe. A "Port" is essentially either a PCIe lane or SAS. So a 8 port card can be 2 x4 or 8 x1 (max 4 per device, same as U.2) or 8 SAS or any combination really. I think there are backplane expander type switches but I haven't looked.

MegaRAID 9560-8i

The MegaRAID 9500 series is the industry’s first PCIe Gen4 RAID adapter family, offering PCIe Gen4 host and storage interfaces. The MegaRAID 9560-8i adapter, based on the SAS3908 high-port count PCIe 4.0 x8 RAID-on-Chip (RoC), delivers twice the performance of previous generations. The 9560-8i...

www.broadcom.com

Intel has rebranded ones etc.

Some light reading on U.3 I found : https://www.storagereview.com/news/evolving-storage-with-sff-ta-1001-u-3-universal-drive-bays

 

[Shadowarez]

thank you ill look this over as im sure once i make this nas itll be time to upgrade drives.

 

[Entz]

As mentioned earlier PCIe lanes is your biggest enemy, I hope AM5 does another industry changing moment (like consumer cores vs enterprise/Hedt) and runs 32+ G5 from the CPU but I am not holding my breath - artificial silos and shareholders and all that.

 

[Shadowarez]

aye gone are the days of having 64 pcie lanes on the cpu.

 

[Sagath]

As mentioned earlier PCIe lanes is your biggest enemy, I hope AM5 does another industry changing moment (like consumer cores vs enterprise/Hedt) and runs 32+ G5 from the CPU but I am not holding my breath - artificial silos and shareholders and all that.

Considering threadrippers have had 64 lanes for (3) generations, I'd take a guess they'll increase it next gen. Will it translate down to consumer? Well we might get the 64 that TR had...

 

[Marzipan]

Considering threadrippers have had 64 lanes for (3) generations, I'd take a guess they'll increase it next gen. Will it translate down to consumer? Well we might get the 64 that TR had...

or 128 lanes if it's a Pro!

 

[Shadowarez]

or Epyc