M.2 Disk

[tim8v]

Hi, I have an X99 system I intend to use for unRAID with some VMs and Plex. I only have one M.2 slot, with a 256Gb drive installed, what would be the best use of this in your opinion? I have 4 x 256Gb SSD's to use in addition to the M.2 drive.

 

[tim8v]

Anybody?

[CHBMB]

Search the forums but I'm not sure if the M2 is fully supported.

[Nicktdot]

M.2 supports both SATA and PCIe interfaces.

 

Do you know which one your system has?

 

 

[CHBMB]

My bad: Ignore me

[tim8v]

thanks, this is a turbo M.2 slot on the board, theoretically giving up to 32Gb/s. I only have one slot, and I asked the question because I thought it was recommended to have two of the same drives if used in the cache pool. ?

[dAigo]

As Nicktdot said, unless we know if your M.2 drive is AHCI or NVME, your question cannot be answered.

M.2 is as vague as an "optical Disk", which could be CD/DVD/BluRay/etc. A Bluray-Disk won't work in a DVD-Drive altouth both are "optical disks"

Unless we know the type of M.2 we can't tell.

 

But you can probably answer your question yourself, after reading this

 

TLDR;

- AHCI "should" work as any other SATA-AHCI SSD

- You can mix any disk in the cache pool, but the slowest drive would set the speed (so mixing M2 with SATA would be a waste)

- NVMe is not yet supported but it "can work" outside of the array.

 

It would be best to be specific about your devices, what manufacturer/model (Mainboard and M.2 Disk) are you using?

[tim8v]

As Nicktdot said, unless we know if your M.2 drive is AHCI or NVME, your question cannot be answered.

M.2 is as vague as an "optical Disk", which could be CD/DVD/BluRay/etc. A Bluray-Disk won't work in a DVD-Drive altouth both are "optical disks"

Unless we know the type of M.2 we can't tell.

 

But you can probably answer your question yourself, after reading this

 

TLDR;

- AHCI "should" work as any other SATA-AHCI SSD

- You can mix any disk in the cache pool, but the slowest drive would set the speed (so mixing M2 with SATA would be a waste)

- NVMe is not yet supported but it "can work" outside of the array.

 

It would be best to be specific about your devices, what manufacturer/model (Mainboard and M.2 Disk) are you using?

 

no worries, sorry.

 

It is an MSI X99A SLI PLUS  http://www.msi.com/product/motherboard/X99A-SLI-PLUS.html#hero-specification

Drive is a Samsung SM951 http://www.samsung.com/semiconductor/products/flash-storage/client-ssd/MZHPV256HDGL?ia=831

[dAigo]

It is an MSI X99A SLI PLUS  http://www.msi.com/product/motherboard/X99A-SLI-PLUS.html#hero-specification

Should work, but something does not add up.

It says quad-sli but only shows up to 3-way config. If you add that up (16x/16x/0x/8x) you would end up using all 40 PCIe-Lanes. (assuming you have a CPU with 40)

So, that SSD + 3-Way SLI may be a Problem. From the datasheet I cannot tell wich lanes/slots are shared.

But you should be safe unless you try 3- or 4-way SLI...

And as I explained in the linked thread, X99 Chipset uses DMI2.0 for the onboard storage connections, which shares a max. of 20GBit/s

So, your 4 SSDs could already be bottlenecked. (in theorie, in real world scenarios, it should be fine)

 

Drive is a Samsung SM951 http://www.samsung.com/semiconductor/products/flash-storage/client-ssd/MZHPV256HDGL?ia=831

MZHPV256HDGL is the AHCI Version. It should be recognized as a "normal" SATA-SSD and therefore work as a cache-drive.

MZVPV256HDGL would be NVMe and would not work in the array right now. (work in progress though)

 

IOPS/Random Access should also be around what the other SSDs could deliver (70k-90k). So you won't waste to much.

But the only thing you problably won't ever see, are the high sequential speeds that drive could reach when left alone.

You would basicly downgrade the M2 disk to a SATA disk when copying massive amount of large files (Backups/Movies/etc)

 

If thats what you are going for you should not mix that drive into the cache pool with the SATA SSDs.

If you want more space in die cache pool and safe a sata port, it should be ok.

[tim8v]

Thanks for the reply. I have a 5920K and a 970 card. So if I wanted to use it on its own, say putting a Windows 10 VM on it, would the I/O speed be ok?

[dAigo]

I guess you mean 5820K.

But yeah, perfomance should be ok, definitly enough for gaming and any other normal Desktop usage.

[JimPhreak]

I have the Samsung SM951 512GB AHCI version SSD in my server and i've tested that it does work in either the array or cache pool.  However I currently have it sitting in my array excluded from all user shares until I figure out the best way to make sure of it.