RAID 0 on Linux

Operating Systems & Open Source Linux
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Id like to find out what issues lie around RAID and linux using the later z170 and z370 chipsets with Intel vs AMD processors.

I am interested in upgraded some components or basically trading the part for a certain feature, in this case, I’d like to get two m.2 slots on my mobo. I only have one atm, I am aware there are adapters, and am wiling to go that route instead of trading the mobo. In any case, there are a few videos of z170 nvme raid 0 with intel and a few with amd, most are older and seems to have some issues or concerns at that time.

Im wondering what has changed in the last two years here… I have not yet found much recent developments on the older tech, just raid with z370 chipset mobos… and I dont have the money for four 960’s … lol

Another thing Id like to discover is if the performance scales with the # of drives installed in the array? Ill google again for some refreshing on the basics of raid. So will two drives work as fast as four drives, in which four drives would just have more storage, or does every drive add performance in the array, meaning I assume to a point: more is better?

In that case, where is the limit. Any videos of a comprehensive benchmark with intel vs amd using raid 0 with the 970 evo vs pro?

Im just starting on the idea of RAID and if its not wise to invest now, Ill invest in the next build, either a later 370 or upcoming 470 chipset or equivalent.

my present mobo has one m.2

Id be willing to get multiple evo’s if they were more than two nvme in the array. just to save on budget. I can always add another in time, so should I plan on a 4 way raid 0 regardless? and just start with the two?

More importantly, how well does linux interact with intel vs amd with raid 0 and the OS being installed directly to that partition?

Can I add multiple arrays, say two for OS and another two for storage? and have four total? two partitions on one array or two separate arrays? cheers for any tips or links you may provide so I can better refine my research.

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What do you need raid 0 nvme for? Youd need some serious hardware to do on board raid 0 and get the full speed benefits. A better bet would be ZFS or BTRFS even then I’m not sure you could get the full benefit.

As far as support goes for hardware raid, im not aware of any on the intel side.

In raid 0 every drive added improves performance and size. With NVME there is going to be diminishing returns. Obviously the trade-off is reliability. If any drive fails the whole array fails. There will be no way to get the data back. Striping is generally regarded as a bad idea.

AFAIK theres no difference really. The biggest determining factor is going to be the raid controller. Installing the OS to that array wouldnt net you a faster OS though. Theres a limit to the return on speeds with the OS. A decent sata drive is going to perform more or less the same as an NVME for general tasks.

sure

yep

its the same as one disk to the OS so whatever you can do to a single disk you can do to the array as a whole

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Interesting, Ill have to check it all out. maybe setting up a budget raid 0 will be in order on the next build. Id want this for fast password recovery and writing - with and to match the performance of the gpu and cpu and ram speeds… I am considering selling present build and start saving for the next release of chipset.

Four ssd in array means though, i dont even have to upgrade my mobo. and I can keep my cpu. I will just use an expansion slot for the drives. I have full support I think via cpu bios mobo just the OS is my real concern. But it does seem that I have to have a 300 series mobo to get it to work…

Here are a few videos I’ve been motivated by:

two nvme raid o with windows ten and a z170 chipset, i7 skylake:

linus talking about 4 way nvme raid 0 and some of the problems here:

Fastest Raid 0 @ 11.87 GBps Samsung NVME 960 Pro x 4:

For Threadripper:

Just found this 3 way setup on a z270 mobo

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Even if you were to generate massive rainbow tables or keep large wordlists the speed of a single NVME should be plenty.

If youre serious about NVME raid, a dedicated controller would be the route I would go. I have my doubts about the effectiveness of on board controllers.

Drivers should be the only thing you need with a dedicated controller.

If you wanted some serious speed ramdisk is where its at but that wouldnt really work for a 500gb wordlist

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NVMe RAID0 on Intel mainstream platform is pointless when one drive almost utilises all of the bandwith of the DMI.
You’d need a PCIe adapter card to go into the CPU directly. At which point the chipset doesn’t handle the RAID anymore AFAIK.

On AMD at least one drive is directly to the CPU, additional drives are through chipset and not PCIe 3.0, or again via adapter card. But there again no chipset RAID.

If you’re planning on NVMe RAID look at an HEDT platform, money shouldn’t be the issue since the drives will be half the cost of the system.

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IIRC this isnt the case anymore. It was only like that early on so they could get dual slots going like on z170 but regardless I dont have faith that the intel RST on board controllers would have the horsepower to handle that throughput on a raid setup because they often struggle with the throughput on normal SSDs

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It still is tho.
Mainstream Platform CPUs have 16 PCIe 3.0 lanes which can be used freely, and 4 lanes for the DMI.

Max # of PCI Express Lanes 16

Of course, as I said, you can still run NVMe drives off of one of the slots (sacrificing GPU lanes), but then the Chipset can’t RAID them. Of course you can then software RAID them.

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I didnt think they were still using DMI for all the m.2 slots but I cant find anything that says otherwise so you’ve got me there. I dont know where I got that idea from. That really sucks.

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On X299 you “can” “technically” go directly to the CPU and do RAID with it, but you need that horribly stupid garbage of a VROC key for it.

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Yea after some digging into it I had to step back for a moment. One nvme is enough as it is my read speeds I am mostly concerned with and they will get bottle necked by the controller or link to the cpu. I should say, one GOOD nvme will do, like the pro variants of Samsung products. I would have to upgrade to a z200 or 3oo series mobo if I wanted RAID 0 to work like these guys and yea AMD has Intel on available pci lanes… so it would be quite the upgrade, the thing is, normal SSD are still pretty close to nvme speeds… even though they are rated higher, the difference in performance is rather minuscule, at least comparing an HDD to an SSD… so as long as I have SSD I should be good to go, though the nvme will be an upgrade.

Ill get one stick of the 500 GB I think… and see how that works with the OS installed and I can use SSD as storage from now on, and get rid of this mechanical drive.