March 2013 Reccomendations for RAID ARRAY editing R3D footage in CS6

[Tim Jones]

Will - I'm using ATTO ExpressSAS H680 on the Mac Pro as well (I mentioned it for the Windows system) and its performance is much faster than the built-in SATA connectivity. Since you're using the built-in bays, you're seeing about what we would expect. Even if you added a 3rd drive, you wouldn't see an increase since you're already getting with the built-in SATA layer provides.

Sorry that I wasn't more clear in my connection options.

As to where you are locating them, that all depends on decisions that you made when you formatted them. By default, the striped pair should show up on your desktop as the name that you provided when you formatted them. You can check this in the Terminal using the "mount" command. For example:

tjones$ mount
/dev/disk0s2 on / (hfs, local, journaled)
devfs on /dev (devfs, local, nobrowse)
/dev/disk1s2 on /Volumes/VD 1 (hfs, local, journaled)

You can see my USB-3 drive (named VD 1) mounted on /Volumes/VD 1

 

[Mike P.]

Just installed my 2x Samsung 840 Pro SSDs and found my speed to be slower than expected.
The 2x SSDs are in a RAID 0. I was expecting to see speeds around 900 MB/s or so. I'm also not able to select my RAID 0 directly, I have to navigate to my user folder to test the drives. I tried to use AJA System test but they don't even show as an option.

Using Mac Pro 2009 (4,1) plugged directly into internal HDD bays 1 & 2.

Write 487 MB/s
Read 509 MB/s

Kinda wondering if I somehow installed my RAID 0 incorrectly.

You could be limited by SATA2 - 3Gbps = 375mb/s theoretical x 2 = ~600mb/s practical…? But, yeah, it also sounds like it might not be set up right… In either case, you should be able to get 400-500meg/s per drive.

 

[Will Keir]

How is the possible? 1300 MB/s using the internal 4 HDD base of the 4,1 Mac Pro? Jeff mentioned the absolute bus limit from SATA II controls is 250 MB/s with a maximum limit of 800 MB/s

You have 4x 1TB Samsung EVO SSDs install in your internal drive sleds in your older Mac Pro. In software Raid 0, created by Disk Utility? How are you connected directly to a Mac Pro? Is your 4x SSD Raid 0 in an external enclosure?

Thanks in advance, trying to understand my Mac Pros limitations better.

I'm using 4, Samsung EVO 840 1TB SSDs in a stripe and seeing a consistent 780MB/sec on a Thunderbolt rig and over 1300MB/sec connected directly to a Mac Pro 4,1.

 

[Will Keir]

Hey thanks Tim.

So I wouldn't expect to see any more speed if I added two more drives. 4x512 Samsung 804 Pro SSDs. I read 800 MB/s is the absolute max on the internal bays, or 250 MB/s each up to 800 MB/s.

Will - I'm using ATTO ExpressSAS H680 on the Mac Pro as well (I mentioned it for the Windows system) and its performance is much faster than the built-in SATA connectivity. Since you're using the built-in bays, you're seeing about what we would expect. Even if you added a 3rd drive, you wouldn't see an increase since you're already getting with the built-in SATA layer provides.

Sorry that I wasn't more clear in my connection options.

As to where you are locating them, that all depends on decisions that you made when you formatted them. By default, the striped pair should show up on your desktop as the name that you provided when you formatted them. You can check this in the Terminal using the "mount" command. For example:

tjones$ mount
/dev/disk0s2 on / (hfs, local, journaled)
devfs on /dev (devfs, local, nobrowse)
/dev/disk1s2 on /Volumes/VD 1 (hfs, local, journaled)

You can see my USB-3 drive (named VD 1) mounted on /Volumes/VD 1

 

[Will Keir]

ah, this is going in circles. Another user said the limit is 250 MB/s per drive because of the SATAII controller. Do you have drives installed that confirm these numbers?

400-500 MB/s per drive would be nice, but I have two installed and only getting 500 MB/s Read/Write.

You could be limited by SATA2 - 3Gbps = 375mb/s theoretical x 2 = ~600mb/s practical…? But, yeah, it also sounds like it might not be set up right… In either case, you should be able to get 400-500meg/s per drive.

 

[Tim Jones]

ah, this is going in circles. Another user said the limit is 250 MB/s per drive because of the SATAII controller. Do you have drives installed that confirm these numbers?

400-500 MB/s per drive would be nice, but I have two installed and only getting 500 MB/s Read/Write.

You really need to get the SSDs into an external chassis (stay away from the Drobo for now) and connect them via true SAS HBA. Of course, I'm spoiled by ATTO, but you can also get good results with Highpoint and Areca so long as you're not using tape devices on the same HBA.

 

[Jeff Kilgroe]

How is the possible? 1300 MB/s using the internal 4 HDD base of the 4,1 Mac Pro? Jeff mentioned the absolute bus limit from SATA II controls is 250 MB/s with a maximum limit of 800 MB/s

You have 4x 1TB Samsung EVO SSDs install in your internal drive sleds in your older Mac Pro. In software Raid 0, created by Disk Utility? How are you connected directly to a Mac Pro? Is your 4x SSD Raid 0 in an external enclosure?

The speed difference has to do with how the SSDs are connected. 3Gbps SATA channels inside the Mac Pro and then a bandwidth ceiling on the integrated SAS host that isn't enough to accommodate all 4 channels at peak at the same time. Tim is talking about speeds connected to a dedicated RAID controller, in this instance the ATTO R680. Two very different setups and the separate controller is most definitely the way to go if you can afford the PCIe slot. In your situation, you would have to give up the HDONE RAID or the CalDigit USB3/eSATA card.

 

[Will Keir]

Gotcha, thanks.

The speed difference has to do with how the SSDs are connected. 3Gbps SATA channels inside the Mac Pro and then a bandwidth ceiling on the integrated SAS host that isn't enough to accommodate all 4 channels at peak at the same time. Tim is talking about speeds connected to a dedicated RAID controller, in this instance the ATTO R680. Two very different setups and the separate controller is most definitely the way to go if you can afford the PCIe slot. In your situation, you would have to give up the HDONE RAID or the CalDigit USB3/eSATA card.