So to summarise my understanding:
As for that M.2 SATA card, I don't read German but the chipset model number suggest that it is a a SATA controller not a port multiplier which is a good thing. But you seem to need three times the number of ports it supplies which means either multiple cards and a PCIe switch or SATA port multiplies.
I've used some of the fomer but, like USB hubs they add ports but do not add bandwidth. I've no experience of the latter but my understanding is that, again, they add ports but not bandwidth.
And guess what? The current bootloader doesn't support booting from a device behind a PCIe switch. No, I don't know when or if that's likely to change though I very much doubt it will.
If you want the tidiness of having everything in a siingle case and if your current enclosures are USB 3 and out of warranty condisder removing the electronics from their cases and mounting them inside the PC case.
- You current NAS uses some model of a PI with 14 HDD in two USB enclosures.
- You want to move the NAS to a Pi 5 or it's on a PI 5 but you want to connect the drives via SATA not USB.
- Your pirmary concern is reducing power comsumption
- You have an old ATX PC case and PSU
- You'd need to purchase aditional hardware and cables.
- You aren't going to reduce power consumption by much if at all. You'll remove the load used by the enclosures but you'll be adding the load used by the SATA adapter(s) and fan(s) in the PSU.
- If your enclosures are USB 3 you'll have less bandwidth (both in total and per drive). The USB controller is inside the RP1 southbridge on a Pi 5 which is connected to the SoC by four PCIe lanes so more than enough bandwith to run both USB root ports at full speed.
On the other hand, the PCIe connector on the Pi 5 only exposes a single lane which is barely enough to run one USB 3 drive or SATA III drive at full speed. - If your current enclosure are doing any sort of hardware (internal to the enclosure) RAID or JBOD you'll lose that. It may or may not be possible to move that to the Linux software RAID tools without a full reformat. I don't know as I've never had to try doing it.
Software RAID will be slower than hardware RAID and put more load onto the Pi's CPU cores. And it increase the volume of data sent to the drives (got/want RAID1? writes go over the bus twice - once for each drive. RAID 5? Again at least twice - once for the data and once for the parity, plus more CPU load for the calculations). - Any perforrmance gained by removing the SATA to USB translation layer may not be noticable with spinning rust drives. The latency in those is prmarily due to the time it takes the heads to move and the platters to rotate into position.
As for that M.2 SATA card, I don't read German but the chipset model number suggest that it is a a SATA controller not a port multiplier which is a good thing. But you seem to need three times the number of ports it supplies which means either multiple cards and a PCIe switch or SATA port multiplies.
I've used some of the fomer but, like USB hubs they add ports but do not add bandwidth. I've no experience of the latter but my understanding is that, again, they add ports but not bandwidth.
And guess what? The current bootloader doesn't support booting from a device behind a PCIe switch. No, I don't know when or if that's likely to change though I very much doubt it will.
If you want the tidiness of having everything in a siingle case and if your current enclosures are USB 3 and out of warranty condisder removing the electronics from their cases and mounting them inside the PC case.
Statistics: Posted by thagrol — Thu Apr 18, 2024 9:42 pm