Mac Pro HD upgrade and RAID 0

[carleton]

I am debating over building my own Vista PC and purchasing a Mac Pro. I have build many a PC, but I am a bit tired of the hassle. The only issue is that I need a number of drives in a RAID 0 and cannot afford to purchase the RAID card from Apple, nor can I justify spending $200 for 500G HD's when I can pick them up for $80.

Are there inexpensive SATA RAID cards that will allow me to strip three drives in the Mac Pro? Does the Mac Pro come with all the hardware one needs to add additional hard drives, or will I need to purchase the hardware?

Carleton

 

[Tallest Skil]

Why is a software RAID unacceptable? Don't ever by hard drives or RAM from Apple.

 

[carleton]

The only purpose in a RAID 0 is speed. Software RAID 0 uses CPU cycles to manage the RAID 0, which slows the system down. All the Windows boards that take the same CPU's that you find on the Mac Pro have basic RAID controllers build in to them. This is one of the big advantages to building my own machine, along with the fact that I can have a case that holds 6 drives rather then 4.

For the record the machine is for HD video editing, so I am looking to have one drive for the OS and most data, all the other ones (3 in a Mac Pro, 5 in my own home built system) be in a RAID 0 for speed.

Carleton

 

[Tom Sawyer]

The only purpose in a RAID 0 is speed. Software RAID 0 uses CPU cycles to manage the RAID 0, which slows the system down. All the Windows boards that take the same CPU's that you find on the Mac Pro have basic RAID controllers build in to them. This is one of the big advantages to building my own machine, along with the fact that I can have a case that holds 6 drives rather then 4.

For the record the machine is for HD video editing, so I am looking to have one drive for the OS and most data, all the other ones (3 in a Mac Pro, 5 in my own home built system) be in a RAID 0 for speed.

Carleton

One advantage of the MP with software raid is that there are 8 cores to help offset the overhead of software raid 0. I'm planning on striping at least two VelociRaptors in the future and as many report the machine performs just fine with that setup. As far as the hardware for adding the drives, sleds for 4 internal drives are included... and if you have built your own rigs in the past then adding a 5th drive in the spare 5 1/4 bay will be a cakewalk. There are 2 unused sata ports on the motherboard. You'll just have to use the standard 3 1/2 to 5 1/4 adapter rails which are a dime a dozen.

When I built my own high end rigs, I used an Areca dedicated PCI-e raid card and it was amazing, but I also was running full Raid 5 (not a viable option with onboard raid controllers on most PC motherboards - they may do it, but the speed is horrible). Are you going to be running Mac OS as well on this or is this going to be a windows only environment? If your target is workstation class hardware, the MP can't be beat bang for the buck wise IMHO. Taking a look at the Dell T7400 Precision with dual quad 2.83ghz, the starting price is $4000 and my guess is building a workstation from workstation class parts (board, quad xeon's etc) will be equally expensive.

There are other options for a dedicated raid card such as the Caldigit card. At $350 or so for the card, they are a better performing alternative to the Apple Raid card.

Hope that helps...

 

[carleton]

If I purchase the Mac, it will be dual boot.

Considering the Adobe software I already own runs in true 64-bit on the Mac, there will be a nice speed increase running on OSX.

I am also a software developer working on my own software. Currently it runs on Windows only, so I need the XP/Vista enviornment to continue that development, but having OSX will finally allow me to port it, which many a customer wants. It is event photography software (http://www.PhotoParata.com) and there are Mac users that want to see it run native on their machines.

Carleton

 

[Horst]

Raid (0) on Mac : look here for some advise on hardware and setup.

More articles at amug.org/ , and then there is barefeats.com , xlr8yourmac.com, and of course the Apple.com forum.
There are a few non-Apple Raid cards which are supposed to work in the MP, have no links ready, though.

You can use 6 harddrives with a MacPro, see my thread a little further down ; 4 will fit in the drive bays provided in the MP enclosure (recent Sata I + II 3.5" HDDs) with no additional hardware required.

I'm no expert here, but, fwiw, I've seen comments that SoftRaid 0 can actually be faster in OSX, with very little CPU overhead, than hardware Raid 0.

Again you can find lots of info on that on the above mentioned websites, I don't have the experience to give you better advice, I'm afraid.

 

[carleton]

Thank you for all the links, I will read over them.

I'm no expert here, but, fwiw, I've seen comments that SoftRaid 0 can actually be faster in OSX, with very little CPU overhead, than hardware Raid 0.

Actually SoftRaid simply is not an option because the machine *WILL* be dual boot and SoftRaid is OSX specific

 

[Umbongo]

The user Nanofrog on here has a good knowledge and experience of RAID and OSX, I'm sure he will post in here but if he doesn't shoot him a PM as I'm sure he would be happy to help you.

 

[Horst]

Thank you for all the links, I will read over them.

Actually SoftRaid simply is not an option because the machine *WILL* be dual boot and SoftRaid is OSX specific

Outch, you want to use the raided HDDs with both OSs ?
Good luck...

 

[carleton]

Well, when the RAID is implemented at the hardware level, both OS's will simply load the drivers for the RAID controller and then will see the RAID drives as one hard drive. In the end, there is no difference to the OS, both only see a single drive.

This is, of course, the whole point in a hardware solution, so the OS is not aware of what is going on. The only gotcha is that there needs to be drivers for both OS's.

Carleton

 

[UltraNEO*]

Well, when the RAID is implemented at the hardware level, both OS's will simply load the drivers for the RAID controller and then will see the RAID drives as one hard drive. In the end, there is no difference to the OS, both only see a single drive.

This is, of course, the whole point in a hardware solution, so the OS is not aware of what is going on. The only gotcha is that there needs to be drivers for both OS's.

Carleton

Wait. Two totally different platforms on one array?

Oh!!! The OS will see a difference, a huge difference! I'm not gonna say nowt from here, seem the OP know's what he/she is doing.

Have fun!

 

[fiercetiger224]

The only purpose in a RAID 0 is speed. Software RAID 0 uses CPU cycles to manage the RAID 0, which slows the system down. All the Windows boards that take the same CPU's that you find on the Mac Pro have basic RAID controllers build in to them. This is one of the big advantages to building my own machine, along with the fact that I can have a case that holds 6 drives rather then 4.

For the record the machine is for HD video editing, so I am looking to have one drive for the OS and most data, all the other ones (3 in a Mac Pro, 5 in my own home built system) be in a RAID 0 for speed.

Carleton

You do know that even if those boards have basic RAID functions, that they're just that, basic. And they're not true hardware RAID. They're really dubbed FakeRAID, which uses a BIOS to trick the system to letting the OS know that it's hardware RAID. It's still software RAID, and it still uses CPU cycles, whether you like it or not.

So in a way, neither solution is going to give you true hardware RAID. The only way to get it is, if you get an expansion card with a hardware RAID controller with a dedicated large memory buffer.

 

[joaoferro37]

You do know that even if those boards have basic RAID functions, that they're just that, basic. And they're not true hardware RAID. They're really dubbed FakeRAID, which uses a BIOS to trick the system to letting the OS know that it's hardware RAID. It's still software RAID, and it still uses CPU cycles, whether you like it or not.

So in a way, neither solution is going to give you true hardware RAID. The only way to get it is, if you get an expansion card with a hardware RAID controller with a dedicated large memory buffer.

I will never use software, got real bad experience on it.
Try a High Point 2314 card (around $179) and get a 4 bay screwless enclosure. Your total cost on a high speed 4TB RAID 5 for MACPro will cost you around 700 dollars. Not only the price is right, the speed is around 230MB/s
RAID card and RAID enclosure:
http://www.amazon.com/RAIDstream-po...3?ie=UTF8&s=electronics&qid=1231358460&sr=8-3
Hard drive, 1TB $79 dollars
http://www.newegg.com/Product/Product.aspx?Item=N82E16822145167&Tpk=0a35155

It is the same HBA as G-Speed ES but a 4TB G-Speed ES is selilng at $1,899

 

[ddevleeschauwer]

by the way how do you measure the hd speed ??
my xbench results are completely different to real file transfer tests ?

i have a macpro 2.88 with 1 OS drive and for data 3 seagate 1.5tb in RAID0
(my osdrive still has to be replaced to 2 velociraptors)

this is the result by xbench

Model MacPro3,1
Drive Type RAID
Disk Test 192.48
Sequential 267.99
Uncached Write 478.24 293.63 MB/sec [4K blocks]
Uncached Write 589.88 333.75 MB/sec [256K blocks]
Uncached Read 103.47 30.28 MB/sec [4K blocks]
Uncached Read 678.10 340.81 MB/sec [256K blocks]
Random 150.16
Uncached Write 57.20 6.05 MB/sec [4K blocks]
Uncached Write 449.56 143.92 MB/sec [256K blocks]
Uncached Read 287.66 2.04 MB/sec [4K blocks]
Uncached Read 289.60 53.74 MB/sec [256K blocks]



while in real life duplicating for example a 20gig folder inside the RAID0 is at about 105mb/sec .....

isn't this very slow ? 105mb/sec for 3 drives stripped in raid0