I'm looking at getting a 48TB RAID. The RAIDs that use hardware controllers (Promise) are considerably more expensive than ones that use software controllers (OWC Thunderbay 4). My question is whether there is a noticeable speed difference. Is there a compelling reasons to spend the extra money for a Promise over an OWC Thunderbay?
Right now I use hard drives of every type, size and connection style. My best HD is a 6TB Promise RAID that moves around 475mb/sec read/write. The OWC Thunderbay 4 claims as high as 1500 mb/sec read., which is WAY faster than the best I have.
Does having a software-controlled RAID impact FCPX in any NOTICEABLE negative way, since it's sharing CPU resources with the RAID?
mindbend wrote: I'm looking at getting a 48TB RAID. The RAIDs that use hardware controllers (Promise) are considerably more expensive than ones that use software controllers (OWC Thunderbay 4). My question is whether there is a noticeable speed difference. Is there a compelling reasons to spend the extra money for a Promise over an OWC Thunderbay?...Does having a software-controlled RAID impact FCPX in any NOTICEABLE negative way, since it's sharing CPU resources with the RAID?
I have an 8TB Promise Pegasus R4 in RAID-5 and three 32TB OWC Thunderbolt 4 arrays, all using SoftRAID. One of those was previously a 16TB array in RAID-5; I upgraded it to 32TB and all three are now in RAID-0. I also have an 8TB OWC SSD array in RAID-0. All the OWC arrays use SoftRAID, even though macOS supports RAID-0 natively. This gives me the option of switching any to a higher RAID format if I want, plus I trust SoftRAID's data integrity and performance more than macOS's AppleRAID.
The Promise arrays are excellent and fairly quiet. However my tests did not show any performance benefit of their hardware RAID vs OWC's software RAID. The OWC arrays aren't as quiet but they aren't loud.
Another big advantage of SoftRAID is avoiding lock-in to a proprietary hardware vendor. If I need to pull the drives from my Promise array, they can't be used in any other chassis without reformatting. The Promise hardware RAID format is proprietary. By contrast if I someday don't like OWC, I can pull those drives and use them without losing data in an Akito, Lacie or any other software RAID box.
Promise has a rigid, limited approval list for what drives are supported in a given raid chassis. This even includes what firmware version is on the drive. It's likely due to the low-level interaction between their microcontroller and the HDDs. OWC and SoftRAID don't have those restrictions.
The Promise Pegasys R4 had extremely slow rebuild times, (aka as RAID sync times). If you lost a drive in RAID-5 it might take several days to rebuild that, during which performance was drastically degraded. A few years ago I did many tests on multiple R4 chassis and documented the data here:
I didn't save the similar data from my rebuild tests on the OWC Thunderbay 4 in RAID-5 using SoftRAID, but I recall it was much faster.
It's possible Promise has improved their rebuild or sync performance on newer models. Promise makes a very good product, I just like the additional flexibility of the OWC arrays. There is no significant host CPU overhead from running SoftRAID, and in fact the entire system seems faster. The SoftRAID utility is easier to use and gives better feedback on drive status than the equivalent Promise Utility.
The Promise Pegasus R8 supports up to 8 drives, so 8 x 6TB drives = 48TB. However you'd normally run that in RAID-6 (double parity) which reduces capacity to 36TB. It gives 6x read speed and no write speed improvement over a single drive. All RAID systems must be fully backed up, so the cost of the backup method must be included.
For significantly less money than the Pegasus R8 you could get TWO 32TB OWC Thunderbay 4s, run them in RAID-0 with one as a backup. This would give almost the same read performance as the R8 in RAID6 and 4x the write performance -- PLUS provide a backup. The backup could be done via Carbon Copy at night or continuously using Time Machine, or various other ways.
Thanks for the great info! It looks like performance isn't really an issue, at least for me. Of all things, it might come down to noise. I really hate noisy equipment. I might order an OWC from B&H and return it if it's too loud. I love their no hassle return policy.
I have two OWC RAIDs and had a Pegasus R6 previously. Performance is on par.
As for noise, I assume people in this thread are talking about disk access noise. That is more a function of the type of mechanisms used in the RAID. My mechanical OWC uses HGST/Toshiba MD04 series drives, which admittedly are a bit too chattery/gronky when reading and writing for my liking. Luckily, I can keep the RAID in an adjacent room. But, a Pegasus RAID using the same drives will be just as loud. And you can always load up a bare OWC enclosure with whatever quiet drives you like (or whatever Promise is using). The fan noise on the OWC is acceptable to me – and can always be improved by swapping out the fan with a premium fan if you're super picky.
My previous Promise R6 was populated with a batch of those horrible Seagate 3TB mechanisms released just after the flood. I had 4 of the 6 of them die on me during the lifespan of that RAID. Remember, the RAID manufacturers are at the mercy of the drive manufacturers.
FCPX.guru wrote: The noise from my OWC RAID is the fan, really super loud.
Some early production OWC Thunderbay 4 units had loud fans. The more recent ones have much quieter fans. You could probably replace it yourself or contact OWC for a suggestion.
My three 32TB Thunderbay 4s all have the quiet fans, but they still aren't as quiet as the Pegasus. I set the OWC units on some vibration-damping pads, that helps some. The need varies a lot based on the desk and exact drive type used in the array. Some desks act like a "sounding board" for any drive vibration.
I have a 16TB OWC Elite Pro Duo, and it's quite loud when seeking. I think it has two of these HGST 8TB drives in it:
So I'm an idiot. I already have a Pegasus R4. For some insane reason, it did not occur to me to just upgrade it with new drives.
The R4 currently has 4x2TB. Can I just swap those out for 4x12TB? I know it will have to rebuild. I found one person online who rebuilt his by replacing one HD at a time, letting it rebuild, then moving on to the next. (RAID 5).
mindbend wrote: I found the hard drive compatibility list for the R4 and it turns out the max HD supported is 4TB, so it doesn't seem possible (at least not officially) to upgrade an R4 with 12TB drives...
The R4 has a very tight official HDD compatibility list, however I've used drives not on that list and it still works. I haven't tried > 4 TB HDDs. IMO this is another reason for using SoftRAID and a generic RAID box. With hardware RAID you cannot move your drives to another different-brand chassis without reformatting, plus you have major restrictions on what HDDs are compatible. I really like the Promise products from an engineering standpoint, I just don't like all the restrictions.
FCPX.guru wrote: Personally, I've never had a need to move my RAID array to a new enclosure. Thus I'm curious, when that becomes necessary? It is an interesting situation.
Over the years I've had several enclosures fail or develop suspected problems where troubleshooting required moving the drives to another enclosure. I went through three Pegasus R4 enclosures.
Sometimes the issues are pedestrian but they still happen. E.g, I had an OWC Thunderbay 4 enclosure where the fan chassis started making noise due to a loose screw. I took it apart to tighten it and almost stripped the final screw head holding the fan chassis, which would have made the fan unusable, thereby making the drive unusable and forcing me to move the drives to another chassis. Fortunately I used a screw extractor to remove it and all was well.
Another situation is if you just want to upgrade to a different brand drive enclosure. With SoftRAID you can just pull the drives and put them in the new enclosure without data loss. With a proprietary hardware RAID format, you are locked into that one vendor unless you back up the array (which normally must be double backed up due to risk), reformat on the new enclosure, then restore the data.
Even collectively these situations don't happen that often, but if you have a bunch of arrays it happens now and then.