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Software RAID versus hardware RAID
- Thread starter strausd
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There are 3rd party brands that will work, and are far far far better than Apple's RAID Pro (which is a total POS). CalDigit is junk as well.
Stick with Areca, ATTO, or in a pinch, Highpoint's RR43xx series (ODM'ed by Areca), but Highpoint's support is truly lousy, so you'd need to know what you're doing. Even getting firmware is difficult (EFI code in order to boot OS X), as their website is a mess (wrong files according to others that have bought them). Once they were up and running however, they're fine.
All three of these companies offer models that not only work under OS X (other OS's too, while in the MP = driver support), but can boot as well once you flash the the card's firmware to EFI boot (if you do this, it can only boot OS X though). Conversely, if you leave it with the BIOS boot section in tact, it can boot Windows and Linux (just not OS X).
If you wanted a card for an OS array for multiple OS's, you'd need 2x cards, as no card out there can boot in both BIOS and EFI (reside in the ROM simultaneously). You could try to flash back and forth, but the firmware ROM can only be written to so many times (MLC = 1E4).
Areca ARC-1210.
Put the 2x drives in the empty optical bay, and it uses SATA cables. Use a Y splitter to get power (not sure of your system, so it's either Molex, or a SATA version - rather easy).
The card will work with up to 4x mechanical, but I'd stick to 2x if you're running fast SSD's.
It's also the least expensive card that can do this (it can boot OS X if that's what you need).
There's ready-made solutions (MaxUpgrades or Transintl), or you can DIY something.
One example of a DIY solution, is to use an old optical drive (prefferably DOA), and disassemble it for the metal plates. One of them will hold 2x 3.5" drives once you drill a few holes.
Clean PCB, thin hobby plywood (found in Hobby Shops), or plexiglass would be additional materials you could use. Just use your imagination (and it keeps the cost far lower).
The drives are just physically mounted there. Power is taken from the power portion of the cable (Molex in the '06 - '08 systems, Backplane cable in the '09 & newer, as that aspect will remain the same).
The data side of the OEM cables will NOT be used. You run SATA cables from the drives to the ARC-1210. If you use a different model, there's going to be a breakout cable (SFF-8087 to 4i*SATA, which is included in Areca's offerings with internal ports).
Here's a pic of a breakout cable, but remember, if you use the ARC-1210, you won't need it.
Attachments
It can be done (3rd party card capable of using drives in the HDD bays), but it will require a different model RAID card (uses SFF-8087 connectors, which is the single, large connector in the pic posted previously). They're more expensive (closest match, is the ARC-1212). In the case of a 4 port model, it's not bad, but as you go up in ports, the cost will increase (i.e. 8/12/16/24 port models). They come with other features as well however, which does offer a good value for the money.
And depending on the system, you'll need either an adapter kit ('09 systems; $165USD here), or possibly an extension cable ('06 - '08 systems; $75USD here).
What I've linked are the least expensive models (4 port).
A. ARC-1210 = you use normal SATA connectors for data and a Y splitter to get power to the drives. You also need to mount them in the optical bay.
B. ARC-1212 = use the included breakout cable, and a Y splitter for power. Again, you still need to mount the drives (optical bay).
There is an option to use the HDD bays, but depending on the system, you will need an adapter of some sort (allows you to use 4x drives).
In almost every case, you have to find a means to provide power and a mounting solution is needed (optical bay or HDD bays).
This will be the case with any 3rd party card.
Of the pair, the ARC-1210 and subsequent parts are the least expensive, nor is it that hard to do. The ARC-1212 can offer you additional flexibility and a faster processor (extremely important if you want to run more than 2x SSD's in a stripe set). Mechanical is fine with either in a stripe set. If you move to a parity array, the ARC-1212 will be the faster card.
I'll let nano confirm this, but from what I've heard, RAID0 speeds are very similar between soft or hard RAID.
Loa
I reckon you won't see any difference at all, since 3D rendering mainly depends on the CPU and not on the hard drive.
And the difference of a two drive RAID0 soft vs. hard is actually neglectable if you ask me. Of course cached throughput will be significantly higher for a hardware RAID but that depends on the cache size. If I recall the ARC 1210 has "only" 256MB cache which means that the throughput of larger files won't be noticeably faster on a hardware solution.
In the case of OS X and the ARC-1210, No, there won't be a massive difference. Cache helps, but it also depends on the usage (i.e. sequential files will benefit, random access, not so much, as the throughputs are reduced to all the seeks needed to find the data).
Now if we were talking about a large quantity of drives (including SSD's) on say an ARC-1680ix8/12/16/24 (cache is on a DIMM), then with upgraded cache (4GB max), it makes a much more notable difference (best balance of performance and cost = 2GB, as the cache performance isn't linear).
What the ARC-1210 will do, is:
1. Allow the array to take the SSD bandwidth off of the chipset, leaving it for mechanical disks which will prevent throttling under simultaneous access.
2. Easy to move from one system to another.
3. Works in multiple OS's (if that matters to strausd).
If none of this is needed, then it's best to go with OS X, but from the information given, the card would be beneficial for reason #1 alone.
Yes, but if you wish to boot, you'd only be able to boot one or the other, not both off of the array. Linux drivers are good too. That's another reason why it's a top rated brand (flexible, stable, and good performance).
Ideally, you'd want to make sure you've plenty of space in each partition to allow enough unused capacity for wear leveling with SSD's. You can even go with separate arrays, but of course it costs more (better redundancy, as if you have a failed array, the other OS isn't taken with it, since you'll be using a stripe set).
Nothing would show up, as that wouldn't work (I don't recall a fix for this).
You CANNOT run a Windows disk on a RAID set via Boot Camp (created under Disk Utility).
Now it should be possible to use a separate disk for Windows, but that doesn't work either (I dont recall any posts on this being fixed). It won't recognize a Windows install on the logic board unless the RAID set is removed from Disk Utility first, then installed.
The simplest and least expensive solution to use OS X's RAID functions + Windows disk, is to use a PCIe SATA card, of which I've found exactly one (SIL3132 based card, that allows you to set the ports as internal, external, or 1+1). The array is on the logic board, and the card can boot Windows. It even has drivers that allow it to work under OS X (from the chip maker, Silicon Image).
It's super cheap, and you'd need to get a data cable (standard SATA) and power to the drive (would need to be mounted in the empty optical bay, or externally). But you must also have a separate drive.
Another option would be to use either USB or FW800 ports via an applicable external enclosure. But the SATA or eSATA method is a better way to go IMO, as it's capable of faster throughputs (can handle SSD's).
It seems like it may actually be better to get a non Apple RAID card because I can then just put the drives in the optical bay and keep more HDD bays open. Then the MP is capable of more than 8TB of storage. Thanks for all your advice nanofrog, you have been extremely helpful!
NP. The only reason to consider a RAID card in your case, was due to the intended usage of SSD's (removes their bandwidth requirments from the ICH and places it on the PCIe bus instead).
Leaving them on the ICH, could put you in a position you'd have performance issues (throttling = not enough bandwidth to handle the drives in use, such as an SSD stripe set + HDD stripe set running at the same time).
If you're not going to be running mulitple RAIDs (or need access to them in multiple OS's), then you may not need to bother. Just go with the most recent possible solution (RAID = OS X's Disk Utility, Windows = SATA card and separate HDD).
And this works?
Didn't work for my but that might be due to a bad SIL card.
I just wanna make sure that the OP won't experience the same issues I had with booting Windows from a SIL based card in the Mac Pro.
AFAIK, it would work due to the BIOS emulation (system) and BIOS on the SIL3132 card.
If there's something going on, I'm not aware of it (I seem to recall you were a special case, as I can't recall anyone else having an issue).
BTW, did you check the card's firmware (updated)?
(Silicon Image has firmware files as well as drivers).