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SATA just needs to be retired. It's already been replaced, we don't need Yet Another Storage Interface. Considering consumer IO-Chipsets are already implemented

by 0manrho 10mo ago

SATA just needs to be retired. It's already been replaced, we don't need Yet Another Storage Interface. Considering consumer IO-Chipsets are already implemented in such a way that they take 4 (or generally, a few) upstream lanes of $CurrentGenPCIe to the CPU, and bifurcating/multiplexing it out (providing USB, SATA, NVMe, etc I/O), we should just remove the SATA cost/manufacturing overhead entirely, and focusing on keeping the cost of keeping that PCIe switching/chipset down for consumers (and stop double-stacking chipsets AMD, motherboards are pricey enough). Or even just integrating better bifurcation support on the CPU's themselves as some already support it (typically via converting x16 on the "top"/"first" PCIe slot to x4/x4/x4/x4). Going forward, SAS should just replace SATA where NVMe PCIe is for some reason a problem (eg price), even on the consumer side, as it would still support existing legacy SATA devices. Storage related interfaces (I'm aware there's some overlap here, but point is, there's already plenty of options, and lots of nuances to deal with already, let's not add to it without good reason): - NVMe PCIe - M.2 and all of it's keys/lengths/clearances - U.2 (SFF-8639) and U.3 (SFF-TA-1001) - EDSFF (which is a very large family of things) - FibreChannel - SAS and all of it's permutations - Oculink - MCIO - Let's not forget USB4/Thunderbolt supporting Tunnelling of PCIe Obligatory: https://imgs.xkcd.com/comics/standards_2x.png https://imgs.xkcd.com/comics/standards_2x.png

saltcured 10mo ago
I think it's becoming reasonable to think consumer storage could be a limited number of soldered NVMe and NVMe-over-M.2 slots, complemented by contemporary USB for more expansion. That USB expansion might be some kind of JBOD chassis, whether that is a pile of SATA or additional M.2 drives. The main problem is having proper translation of device management features, e.g. SMART diagnostics or similar getting back to the host. But from a performance perspective, it seems reasonable to switch to USB once you are multiplexing drives over the same, limited IO channels from the CPU to expand capacity rather than bandwidth. Once you get out of this smallest consumer expansion scenario, I think NAS takes over as the most sensible architecture for small office/home office settings. Other SAN variants really only make sense in datacenter architectures where you are trying to optimize for very well-defined server/storage traffic patterns. Is there any drawback to going towards USB for multiplexed storage inside a desktop PC or NAS chassis too? It feels like the days of RAID cards are over, given the desire for host-managed, software-defined storage abstractions. Does SAS still have some benefit here?
- wtallis 10mo ago
  I wouldn't trust any USB-attached storage to be reliable enough for anything more than periodic incremental backups and verification scrubs. USB devices disappear from the bus too often for me to want to rely on them for online storage.
  - saltcured 10mo ago
    OK, I see that is a potential downside. I can actually remember way back when we used to see sporadic disconnects and bus resets for IDE drives in Linux and it would recover and keep going. I wonder what it would take to get the same behavior out of USB as for other "internal" interconnects, i.e. say this is attached storage and do retry/reconnect instead of deciding any ephemeral disconnect is a "removal event"...? FWIW, I've actually got a 1 TB Samsung "pro" NVMe/M.2 drive in an external case, currently attached to a spare Ryzen-based Thinkpad via USB-C. I'm using it as an alternate boot drive to store and play Linux Steam games. It performs quite well. I'd say is qualitatively like the OEM internal NVMe drive when doing disk-intensive things, but maybe that is bottlenecked by the Linux LUKS full-disk encryption? Also, this is essentially a docked desktop setup. There's nothing jostling the USB cable to the SSD.
- pdimitar 10mo ago
  As @wtallis already said, a lot of external USB stuff is just unreliable. Right now I am overlooking my display and seeing 4 different USB-A hubs and 3 different enclosures that I am not sure what to do with (likely can't even sell them, they'd go for like 10-20 EUR and deliveries go for 5 EUR so why bother; I'll likely just dump them at one point). _All_ of them were marketed as 24/7, not needing cooling etc. _All_ of them could not last two hours of constant hammering and it was not even a load at 100% of the bus; more like 60-70%. All began disappearing and reappearing every few minutes (I am presuming after overheating subsided). Additionally, for my future workstation at least I want everything inside. If I get an [e]ATX motherboard and the PC case for it then it would feel like a half-solution if I then have to stack a few drives or NAS-like enclosures at the side. And yeah I don't have a huge villa. Desk space can become a problem and I don't have cabinets or closets / storerooms either. SATA SSDs fill a very valid niche to this day: quieter and less power-hungry and smaller NAS-like machines. Sure, not mainstream, I get how giants like Samsung think, but to claim they are no longer desirable tech like many in this thread do is a bit misinformed.

by 0manrho 10mo ago

saltcured 10mo ago

I think it's becoming reasonable to think consumer storage could be a limited number of soldered NVMe and NVMe-over-M.2 slots, complemented by contemporary USB for more expansion. That USB expansion might be some kind of JBOD chassis, whether that is a pile of SATA or additional M.2 drives. The main problem is having proper translation of device management features, e.g. SMART diagnostics or similar getting back to the host. But from a performance perspective, it seems reasonable to switch to USB once you are multiplexing drives over the same, limited IO channels from the CPU to expand capacity rather than bandwidth. Once you get out of this smallest consumer expansion scenario, I think NAS takes over as the most sensible architecture for small office/home office settings. Other SAN variants really only make sense in datacenter architectures where you are trying to optimize for very well-defined server/storage traffic patterns. Is there any drawback to going towards USB for multiplexed storage inside a desktop PC or NAS chassis too? It feels like the days of RAID cards are over, given the desire for host-managed, software-defined storage abstractions. Does SAS still have some benefit here?

wtallis 10mo ago
I wouldn't trust any USB-attached storage to be reliable enough for anything more than periodic incremental backups and verification scrubs. USB devices disappear from the bus too often for me to want to rely on them for online storage.
- saltcured 10mo ago
  OK, I see that is a potential downside. I can actually remember way back when we used to see sporadic disconnects and bus resets for IDE drives in Linux and it would recover and keep going. I wonder what it would take to get the same behavior out of USB as for other "internal" interconnects, i.e. say this is attached storage and do retry/reconnect instead of deciding any ephemeral disconnect is a "removal event"...? FWIW, I've actually got a 1 TB Samsung "pro" NVMe/M.2 drive in an external case, currently attached to a spare Ryzen-based Thinkpad via USB-C. I'm using it as an alternate boot drive to store and play Linux Steam games. It performs quite well. I'd say is qualitatively like the OEM internal NVMe drive when doing disk-intensive things, but maybe that is bottlenecked by the Linux LUKS full-disk encryption? Also, this is essentially a docked desktop setup. There's nothing jostling the USB cable to the SSD.
pdimitar 10mo ago
As @wtallis already said, a lot of external USB stuff is just unreliable. Right now I am overlooking my display and seeing 4 different USB-A hubs and 3 different enclosures that I am not sure what to do with (likely can't even sell them, they'd go for like 10-20 EUR and deliveries go for 5 EUR so why bother; I'll likely just dump them at one point). _All_ of them were marketed as 24/7, not needing cooling etc. _All_ of them could not last two hours of constant hammering and it was not even a load at 100% of the bus; more like 60-70%. All began disappearing and reappearing every few minutes (I am presuming after overheating subsided). Additionally, for my future workstation at least I want everything inside. If I get an [e]ATX motherboard and the PC case for it then it would feel like a half-solution if I then have to stack a few drives or NAS-like enclosures at the side. And yeah I don't have a huge villa. Desk space can become a problem and I don't have cabinets or closets / storerooms either. SATA SSDs fill a very valid niche to this day: quieter and less power-hungry and smaller NAS-like machines. Sure, not mainstream, I get how giants like Samsung think, but to claim they are no longer desirable tech like many in this thread do is a bit misinformed.