twotwotwo

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Dunno about those drive suggestions: you'd be paying for extra GB/s you couldn't use through TB3. Four WD Blues/Intel 665p's still move 40Gb/s easily but might save you $100 (across the four sticks) vs. the suggested higher-end choices.

(Yay for consumer NVMe RAID though, at ~10c/GB it's not such a wild/niche idea!)
 

twotwotwo

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I guess I shouldn't've said a declarative sentence on the Internet if I didn't want an argument but: you might want more Flash than is cost-effectively available in a single drive, and RAID can be a convenient way to access multiple drives and take advantage of their combined throughput. (In other contexts it can help with hardware reliability, though that wouldn't be the case with this enclosure, which is RAID 0.)

I'm not saying you or me or everyone should do it, but doesn't seem outlandish!
 

USAFRet

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I guess I shouldn't've said a declarative sentence on the Internet if I didn't want an argument but: you might want more Flash than is cost-effectively available in a single drive, and RAID can be a convenient way to access multiple drives and take advantage of their combined throughput. (In other contexts it can help with hardware reliability, though that wouldn't be the case with this enclosure, which is RAID 0.)

I'm not saying you or me or everyone should do it, but doesn't seem outlandish!
No, not an argument.

But we've seen many many people with the desire for a RAID 0 + NVMe, simply because they heard the term RAID 0, and that it is magically faster.
Outside very rare use cases, it isn't.
 

escksu

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Thundebolt is essential PCIE 3.0 x4. Same as nvme. The problem is that this is limited to 4GB/s.... Thats why PCIE 3.0 nvme drives can't go higher, need PCIE 4.0

So, I don't see how this RAID can overcome this 4GB/s bottleneck.
 

junglist724

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Thundebolt is essential PCIE 3.0 x4. Same as nvme. The problem is that this is limited to 4GB/s.... Thats why PCIE 3.0 nvme drives can't go higher, need PCIE 4.0

So, I don't see how this RAID can overcome this 4GB/s bottleneck.
Yeah wtf is the point of putting 16 lanes worth of SSDs in an enclosure that is connected to your pc by 4 lanes.
 

twotwotwo

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Yeah wtf is the point of putting 16 lanes worth of SSDs in an enclosure that is connected to your pc by 4 lanes.
I think the trick is to fill it with lower-end NVMe drives that each move less than 4 GB/s, and then combined you can have 4-8 TB at...a decent number of GB/s for your MacBook Pro or whatever, while paying ~10c/GB for lower end SSDs. If they don't wildly overprice the enclosure, it could beat a lot of current TB3 SSDs on price.

Of course, you don't have to buy it if that doesn't do anything for you. I don't have TB3 and haven't filled the one internal SSD on this laptop, so...
 
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spongiemaster

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Thundebolt is essential PCIE 3.0 x4. Same as nvme. The problem is that this is limited to 4GB/s.... Thats why PCIE 3.0 nvme drives can't go higher, need PCIE 4.0

So, I don't see how this RAID can overcome this 4GB/s bottleneck.
It can't. The spec page says that a single drive tops out around 750MB/s which isn't great. USB 3.2 peaks around 1000MB/s with an NVME drive. So, speed is getting lost somewhere along the line for each drive. With RAID, speed can increase to 2550MB/s, which is pretty decent for an external drive.
 

joevt1

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It can't. The spec page says that a single drive tops out around 750MB/s which isn't great. USB 3.2 peaks around 1000MB/s with an NVME drive. So, speed is getting lost somewhere along the line for each drive. With RAID, speed can increase to 2550MB/s, which is pretty decent for an external drive.
Right. This is the same configuration as the OWC Express 4M2. One PCIe 3.0 x1 lane per NVMe with a DisplayPort 1.2 output (OP incorrectly says DisplayPort 1.4).
The reason for only one lane per NVMe is for cost. The single lanes come from the Alpine Ridge Thunderbolt controller directly. To get 4 lanes per NVMe would require a PCIe 3.0 switch with at least 20 lanes which is very expensive.
The point of these enclosures is capacity but it can also do performance with software RAID. With software RAID, you can actually get better performance than with an enclosure with a single x4 NVMe because those usually have poor write speed (down to 800 MB/s for some) compared to read speed (2500 MB/s) while in a Thunderbolt enclosure (Thunderbolt is limited to ~2750 MB/s). With Software RAID, even if the write performance per NVMe is low, it adds up. I don't know of a single NVMe that has good write performance in a x4 Thunderbolt enclosure - these x1x1x1x1 Thunderbolt enclosures can fix that problem. Would be nice to see some benchmarks to be sure.

As for USB 3.1 gen 2 (10 Gbps) remember there are the ASMedia ASM1142 controllers that are also limited to 750 MB/s because of the PCIe connection (either PCIe 2.0 x2 or PCIe 3.0 x1). You need a USB controller with PCIe 3.0 x2 or greater to get the 1000 MB/s numbers.
 

Lostinlodos

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Just one question? JBOD?
I don’t care about raid.

I currently use internal SATA SSDs with SATA to usb 3.1/3.2 plugged in to a USB3x hub connected to my Mac via USB3. Adding 4 drives to a single port would be nice. If I can do away with the raid nonsense.

Yes I know the what and why of raid, I prefer the oldskool backup methodology. right or wrong I see raid as another level of failure points. And avoid it.
 

twotwotwo

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Just one question? JBOD?
It looks like it is a JBOD, likely just relaying one lane of PCIe (at about 750 MB/s) to/from each m.2 stick. The page the story is based on mentions software RAID. joevt1's comment seems like the best summary of what's going on and you can look up the similar OWC enclosure already out there--this looks smaller and be nice if it was cheaper, too.
 

Lostinlodos

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Thanks. Twotwotwo for the fast reply.
looking through the web page linked it appears to be quite limited in support info. I haven’t dug through the manual yet. But so far it matches the EVO line of Samsung NvMe drives I’d use.
I can’t find anything on site limits or raid options. But software raid can usually be disabled.
 

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