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strausd
Apr 20, 2010, 10:09 PM
Hey guys, I am planning on getting a 2010 MP when they come and have a question about it. I am 90% sure that with my budget, I will not be able to after a RAID card. I am wondering if software RAID would be alright or if it's so bad it's not worth doing. Also, there is small chance that I could buy a RAID card later on, how would I install it? I will be using it for 3D animation with Maya and some zbrush modeling. Also I will be doing some Photoshop and illustrator and maybe some gaming on win 7 boot camp. Feel free to list any other pros and cons about either a software RAID or hardware RAID, I wana make sure I have all the details before making a final decision on it. Thanks for all the help in advance!



Decrepit
Apr 20, 2010, 10:13 PM
Hey guys, I am planning on getting a 2010 MP when they come and have a question about it. I am 90% sure that with my budget, I will not be able to after a RAID card. I am wondering if software RAID would be alright or if it's so bad it's not worth doing. Also, there is small chance that I could buy a RAID card later on, how would I install it? I will be using it for 3D animation with Maya and some zbrush modeling. Also I will be doing some Photoshop and illustrator and maybe some gaming on win 7 boot camp. Feel free to list any other pros and cons about either a software RAID or hardware RAID, I wana make sure I have all the details before making a final decision on it. Thanks for all the help in advance!

My recommendation would be to just do software raid 0 for highest performance AND BACK UP BACK UP BACK UP BACK UP BACK UP.

And BACK UP.

With Time Machine, you can be backing up to another location at your place. You might consider a second backup program that backs up your data to another location/site. If it's really important, make sure you can get it back even if your house burns down.

You don't need to be able to recover your operating system in a catastrophic event. You can go buy another Mac Pro with your insurance check. But your data is priceless, so it should be kept in at least two locations.

strausd
Apr 20, 2010, 10:31 PM
What are the cons of a software RAID and how is it done?

Decrepit
Apr 20, 2010, 10:41 PM
I haven't been able to try it on a Mac yet, my experience comes from the server world.

But software RAID basically means that the computer handles the splitting up of the files instead of a dedicated controller.

Hardware is the only way to go for important arrays. RAID 5, 6, etc. But for straight performance, there's no math involved, so the CPU can handle it.

One of the resident Mac Pro owners will be able to give you an easy rundown.

But in case I didn't mention it before, do your backups, and don't just rely on Time Machine. Time Machine is awesome. But it doesn't offer you offsite recovery. If you're spending the cash on a Mac Pro for real work, do the homework on a backup solution.

Gonk42
Apr 21, 2010, 02:37 AM
Assuming the 2010 Pro has 12 or 6 cores, there are plenty to spare to cope with the overhead of software raid. One thing that more expensive raid cards have is large buffers. I don't know if the software raid uses RAM as a buffer in the same way - I'd assume it does. I've been told that for a powerful workstation like the Mac Pro with plenty of cores and RAM, software raid is as good, or even better, than hardware raid (certainly for raid 0).

Angelo95210
Apr 21, 2010, 02:49 AM
Software backup is recommended in case you need to start up quickly after an incident like a hd crash. It's not a backup solution as you know, so I would go for two spare hd drives for backup, one with TM the second one with SuperDuper or CarbonCopyCloner.

strausd
Apr 21, 2010, 08:31 AM
How do you even do a software RAID on a Mac Pro?

gotzero
Apr 21, 2010, 09:54 AM
How do you even do a software RAID on a Mac Pro?

It is easy to set up is Disk Utility. I am all software RAID on my systems, never had an issue.

I have RAID 5 systems, but they are all external. Anything actually in the machines are simple stripes.

strausd
Apr 21, 2010, 10:51 AM
Would a software RAID 0 be just as fast as a hardware RAID 0?

brendon2020
Apr 21, 2010, 11:36 AM
before you install mac os x you have to configure the raid. I haven't been able to figure it out an existing install. You can redo it from time machine though. You go into disk util when you boot off the install disk, you create the mirror raid then drag to two disks to the raid, then you install the os.

If the raid breaks, you have to boot off the install disk and open up disk util and it'll start repairing (which will take a long time, over night usually).

It works fairly well, its worth it since reinstalling from time machine can take over night.

nanofrog
Apr 21, 2010, 01:37 PM
It is easy to set up is Disk Utility. I am all software RAID on my systems, never had an issue.

I have RAID 5 systems, but they are all external. Anything actually in the machines are simple stripes.
Software implementations of parity arrays = Really Bad Idea, as it can't handle the write hole issue. Hardware controllers use an NVRAM solution in conjunction with a card battery to solve it.

And a UPS is a necessity as well (and does more than the card battery). Ideally, you run both (UPS + card battery), but I've seen budget restrictions far too often, and if you're forced to only get one, go for the UPS.

Even in the enterprise world, the card battery is typically skipped, but the power systems implemented are far more extensive than just a UPS as well (redundant UPS + redundant generators; n+1 configuration at a minimum).

Would a software RAID 0 be just as fast as a hardware RAID 0?
Not quite. A stripe set is a low demand form of RAID on the processor, but the cache on the hardware cards can make a difference, and with some cards (expandable cache), it's quite notable.

But there's a notable cost difference as well. Not just for the card, but you typically have to run enterprise HDD's rather than consumer models (which can be used in a software RAID, as the control is retained by the system rather than the card). So the recovery timings in the consumer models will work.

That said, enterprise drives are a good idea anyway, as they're rated better, and have additional sensors that prevent the heads from physically crashing into the platters.

I haven't been able to figure it out an existing install.
You can't, as the inititalization process "carves" the disks up into stripes. In doing so, any existing data on them is destroyed.

gotzero
Apr 21, 2010, 02:13 PM
Software implementations of parity arrays = Really Bad Idea, as it can't handle the write hole issue. Hardware controllers use an NVRAM solution in conjunction with a card battery to solve it.

I thought I said this, but I guess not. I only run software stripes, which run fine for me. All of the RAID5 systems are external with their own controllers.

I think it is fine to run a software mirror, but anything more extensive should probably be hardware.

nanofrog
Apr 21, 2010, 02:26 PM
I thought I said this, but I guess not. I only run software stripes, which run fine for me. All of the RAID5 systems are external with their own controllers.

I think it is fine to run a software mirror, but anything more extensive should probably be hardware.
Software can function correctly for 0/1/10, though there are reasons for using a hardware controller for these levels as well (but it's not always a necessity, and dependent on the specifics).

It's parity levels that software hasn't the full ability to operate properly. When you say the externals have their own controllers, what are they?
eSATA based?
Proper hardware RAID cards?
Or is it a board in the enclosure itself (can be problematic, and really has to be investigated properly)?

Just curious, as you could be less protected than you think.

Rad
Apr 21, 2010, 06:20 PM
I have been running a Apple software RAID 0 with internal WD Raptors since August 2006 in my first generation Mac Pro. I use the computer extensively for both work and play. I have never had a single problem for the entire time - over 3 1/2 years. I do have a regularly updated backup drive via Super Duper. Easy, inexpensive and very fast.

gotzero
Apr 21, 2010, 07:21 PM
Proper hardware RAID cards?
Or is it a board in the enclosure itself (can be problematic, and really has to be investigated properly)?

I have and continue to buy these (http://eshop.macsales.com/shop/hard-drives/RAID/Rack_Mount/FireWire_eSATA_USB2_RAID), three at a time. Of each triplicate, one is operational, one is onsite backup, and one is offsite backup. Each changes place every week or so. I think I am going to be okay. :) However, I do want to kiss whomever came up with quick release rack pins!

For the stuff where speed is not important and data amounts are smaller, I get these (http://eshop.macsales.com/shop/firewire/usb/raid_1/Gmax) in triplicate, same deal as the above, just much easier to move around.

I hope OWC appreciates the amount of business I throw at them!

strausd
Apr 21, 2010, 07:45 PM
What about a software RAID 0 on 2 drives and use time machine to back that up? Is an offsite backup necessary or just a good suggestion?

gotzero
Apr 21, 2010, 07:52 PM
What about a software RAID 0 on 2 drives and use time machine to back that up? Is an offsite backup necessary or just a good suggestion?

I would say that would be fine. That is what I do with my system SSDs. There is not really a need to have a full OS backup these days unless you are concerned about uptime.

The bottom line about backing up is that you can never be paranoid enough. Get to a point where you are comfortable (and your data is safe). Hardware pooping out and damage or theft are different issues. I would always recommend having an offsite backup of at least important personal/work files, but that is probably way overkill for most.

strausd
Apr 21, 2010, 08:01 PM
I think that my most important files and documents will be on my MBP as well which I take everywhere. So in a way it's kind of like an offsite backup. I am planning on not having a SSD as my boot disk because there will be a lot of OS X applications I will be putting on there along with windows 7 boot camp and programs for that. So it seems like there may not be enough space on a SSD for all of that, if there is I don't think my budget will be able to handle it :(

strausd
Apr 21, 2010, 09:19 PM
Also, what kind of performance decrease would I see if i had 2 drive (not my boot drive) on software RAID 0? These drives would hold my 3D documents, animations, and psd's

nanofrog
Apr 22, 2010, 12:15 AM
I have and continue to buy these (http://eshop.macsales.com/shop/hard-drives/RAID/Rack_Mount/FireWire_eSATA_USB2_RAID), three at a time. Of each triplicate, one is operational, one is onsite backup, and one is offsite backup. Each changes place every week or so. I think I am going to be okay. :) However, I do want to kiss whomever came up with quick release rack pins!

For the stuff where speed is not important and data amounts are smaller, I get these (http://eshop.macsales.com/shop/firewire/usb/raid_1/Gmax) in triplicate, same deal as the above, just much easier to move around.

I hope OWC appreciates the amount of business I throw at them!
Both use Oxford 936 chips (different variants), but are hardware controller SoC's (use ARM processors). So you're definitely better off. :)

Also, what kind of performance decrease would I see if i had 2 drive (not my boot drive) on software RAID 0? These drives would hold my 3D documents, animations, and psd's
Compared to a single disk (HDD) or SSD?

With a stripe set, the throughput = n* the throughput of a single drive. So for n = 2, it's 2x faster than one of the disks used on it's own. This applies to both mechanical or flash, but with flash, you can run into bandwidth issues (aka throttling, but it depends on the specifics, such as how many drives in the set, how many on the same controller, and whether or not they're used simultaneously).

strausd
Apr 22, 2010, 08:18 AM
I wouldnt be able to afford a SSD

nanofrog
Apr 22, 2010, 02:03 PM
I wouldnt be able to afford a SSD
Mechanical stripe sets are faster at sequential throughputs, and slightly at random access (theoretically, it halves, but that's rarely the case, as there's mulitple dependencies that just aren't met under real world conditions).

But it's also less expensive than an SSD, especially when you look at it from a cost/GB POV.

strausd
Apr 22, 2010, 02:53 PM
How difficult is it, if at all, to install a RAID card yourself? There is a chance that I can maybe afford one later during the year

nanofrog
Apr 22, 2010, 03:14 PM
How difficult is it, if at all, to install a RAID card yourself? There is a chance that I can maybe afford one later during the year
Not difficult at all. Just be sure to read the manual carefully, if you're not that confident about it.

Basically, you plug the card in, attach the drives, and fire up the system. Install the drivers, then gain access to the card, and create the array.

But personally, I add a step before creating the array, and that's run a full surface scan of the drives (new or not), to get an idea of the drive's health (i.e. helps find damage due to either poor QC or shipping). Age as well, if they're used.

Once the array is created, then you can transfer data to it. If it's the OS, you re-install from a clone (assuming you've a spare disk for this task, and install the drivers if the clone is made prior to driver installation), or do a clean install if there's no spare drive you can use.

Loa
Apr 22, 2010, 09:34 PM
Mechanical stripe sets are faster at sequential throughputs, and slightly at random access

Did you skip a word between "slightly" and "at", or are you implying that RAIDs of mechanical drives are faster at random access than SSDs?

In my 2009MP, I saw just about the same speed increase going (for my boot volume) from a 4 disk RAID0 to a single SSD, than I saw going from a single mechanical drive to that 4 disk RAID0. (In other words: single HD < 4 disk RAID0 < single SSD)

Isn't random access the defining factor for an OS volume?

Loa

strausd
Apr 22, 2010, 09:56 PM
Not difficult at all. Just be sure to read the manual carefully, if you're not that confident about it.

Basically, you plug the card in, attach the drives, and fire up the system. Install the drivers, then gain access to the card, and create the array.



Does this mean it doesn't have to be one of Apple's RAID cards?

nanofrog
Apr 22, 2010, 11:46 PM
Does this mean it doesn't have to be one of Apple's RAID cards?
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).

strausd
Apr 23, 2010, 08:25 AM
what card would be best for just putting 2 drive on RAID 0 under OS X?

nanofrog
Apr 23, 2010, 12:19 PM
what card would be best for just putting 2 drive on RAID 0 under OS X?
Areca ARC-1210 (http://www.newegg.com/Product/Product.aspx?Item=N82E16816131003&Tpk=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).

strausd
Apr 23, 2010, 02:48 PM
Ya I am planning on getting a 2010 MP and don't want to pay $700 for Apple's RAID card. How would I connect 2 drives to the empty optical bay?

nanofrog
Apr 23, 2010, 04:28 PM
Ya I am planning on getting a 2010 MP and don't want to pay $700 for Apple's RAID card. How would I connect 2 drives to the empty optical bay?
There's ready-made solutions (MaxUpgrades (http://www.maxupgrades.com/istore/index.cfm?fuseaction=product.display&product_id=158) or Transintl (http://www.transintl.com/store/procaddy.cfm)), 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).

strausd
Apr 23, 2010, 05:06 PM
Would I have to connect the HDDs to the optical bay in order for the RAID card to work?

nanofrog
Apr 23, 2010, 08:27 PM
Would I have to connect the HDDs to the optical bay in order for the RAID card to work?
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.

strausd
Apr 24, 2010, 01:49 AM
So if the HDDs have to use SATA cables to plug in to the RAID card does that mean that they can't be put in one of the 4 HDD bays?

nanofrog
Apr 24, 2010, 01:37 PM
So if the HDDs have to use SATA cables to plug in to the RAID card does that mean that they can't be put in one of the 4 HDD bays?
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 (http://www.newegg.com/Product/Product.aspx?Item=N82E16816151038&cm_re=ARC-1212-_-16-151-038-_-Product)). 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 (http://www.maxupgrades.com/istore/index.cfm?fuseaction=product.display&product_id=189%20)), or possibly an extension cable ('06 - '08 systems; $75USD here (http://www.maxupgrades.com/istore/index.cfm?fuseaction=product.display&product_id=177)).

strausd
Apr 25, 2010, 01:44 AM
Is ther a RAID card in which I wouldn't need any other extra pieces besides the card itself? Basically one just like the one Apple offers, just not so crazy of a price...

nanofrog
Apr 25, 2010, 02:43 AM
Is ther a RAID card in which I wouldn't need any other extra pieces besides the card itself? Basically one just like the one Apple offers, just not so crazy of a price...
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.

strausd
Apr 25, 2010, 01:42 PM
So with only 2 HDDs in RAID 0 the 1210 would be the best choice? Would this be crazy fast compared to software RAID or just a little faster?

Loa
Apr 25, 2010, 04:00 PM
So with only 2 HDDs in RAID 0 the 1210 would be the best choice? Would this be crazy fast compared to software RAID or just a little faster?

I'll let nano confirm this, but from what I've heard, RAID0 speeds are very similar between soft or hard RAID.

Loa

strausd
Apr 25, 2010, 04:19 PM
Then if I was putting 2 drives on software RAID 0 and doing 3D rendering on Maya, would I see a performance decrease compared to if I was not doing a software RAID?

Transporteur
Apr 25, 2010, 04:35 PM
Then if I was putting 2 drives on software RAID 0 and doing 3D rendering on Maya, would I see a performance decrease compared to if I was not doing a software RAID?

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.

nanofrog
Apr 25, 2010, 08:33 PM
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.

strausd
Apr 25, 2010, 11:24 PM
I do plan on having a seperate partition for windows 7 because some of the 3D software I will be using is pc only. I am glad to hear that the card works with both. Is the driver support good for both windows 7 and OS X?

nanofrog
Apr 25, 2010, 11:31 PM
I do plan on having a seperate partition for windows 7 because some of the 3D software I will be using is pc only. I am glad to hear that the card works with both. Is the driver support good for both windows 7 and OS X?
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).

strausd
Apr 25, 2010, 11:35 PM
So if I were to set up a RAID 0 on OS X and later put windows 7 on through boot camp, what would show up if I booted up on windows 7? Just 2 2tb drives instead of one 4tb?

nanofrog
Apr 25, 2010, 11:50 PM
So if I were to set up a RAID 0 on OS X and later put windows 7 on through boot camp, what would show up if I booted up on windows 7? Just 2 2tb drives instead of one 4tb?
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 (http://cgi.ebay.com/4-Port-ESATA-SATA-II-PCI-E-PCI-Express-Card-SIL3132-/190391554821?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item2c54389305), 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 (http://www.siliconimage.com/support/searchresults.aspx?pid=32&cat=3&os=3)).

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).

strausd
Apr 26, 2010, 08:52 AM
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!

nanofrog
Apr 26, 2010, 10:54 AM
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!
:cool: 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).

Transporteur
Apr 26, 2010, 11:10 AM
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.

nanofrog
Apr 26, 2010, 11:19 AM
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).

Transporteur
Apr 26, 2010, 11:23 AM
Unfortunately I didn't examine the issue any further, and I don't even use the card for internal drives any more.

But if others have this kind of setup running then there shouldn't be a problem.

nanofrog
Apr 26, 2010, 11:38 AM
Unfortunately I didn't examine the issue any further, and I don't even use the card for internal drives any more.

But if others have this kind of setup running then there shouldn't be a problem.
What exact card did you use?

I'm wondering if it's the firmware, or possibly they didn't use the reference design (i.e. trying to reduce the part count to save costs - there's not much to them though). :confused:

There's other cards, but they're all eSATA ONLY, and means an external enclosure would be needed.

Loa
Apr 26, 2010, 12:10 PM
Hello,

Using a PCI-e card like the sil3132, are there significant speed differences between an eSATA external drive, or that same drive plugged in one of the MP's internal bays?

Loa

P.S. I can't test it myself as I only have RAIDed drives inside my Mac Pro.

Transporteur
Apr 26, 2010, 12:14 PM
What exact card did you use?

I'm wondering if it's the firmware, or possibly they didn't use the reference design (i.e. trying to reduce the part count to save costs - there's not much to them though). :confused:



It's this card: Digitus DS-30102 (http://www.digitus.info/en/products/accessories/?c=1202&p=15606)

Looks pretty much like the reference design, but who knows? :rolleyes:
Does only work with Sonnet drivers, even the drivers they offer don't work with OS 10.6.

Phantom Gremlin
Apr 26, 2010, 05:13 PM
In this entire thread I haven't seen anyone mention the "other" (http://www.softraid.com/index.html) (i.e. not Apple) software RAID.

Is it because nobody wants to pay extra for software when Apple's is "good enough"? Or is it because everyone thinks hardware RAID is the way to go?

Yes I know there are limitations. E.g. no RAID-5. But Apple's software doesn't support that either.

Transporteur
Apr 26, 2010, 05:45 PM
Is it because nobody wants to pay extra for software when Apple's is "good enough"? Or is it because everyone thinks hardware RAID is the way to go?


I haven't heard about this before, but to be honest, what is the major advantage of SoftRaid that makes me wanna pay $70 over using a software RAID that is already implemented, hence fully supported and widely tested in the operating system?

strausd
Apr 26, 2010, 06:10 PM
It probably wasn't mentioned because I was only wondering about RAID 0 which is supported by Apple.

Phantom Gremlin
Apr 26, 2010, 09:38 PM
SoftRAID is $129. It claims: (http://www.softraid.com/vsapple.html) Flexibility, Reliability, and Usability are the three main distinctions between Apple's Disk Utility and SoftRAID 3.

I haven't used Apple's RAID nor SoftRAID. I was hoping someone who has used both would chime in and report if it's "worth it". Obviously it can't be too popular or there would have already been a plethora of postings extolling its virtues.

nanofrog
Apr 27, 2010, 12:03 AM
Using a PCI-e card like the sil3132, are there significant speed differences between an eSATA external drive, or that same drive plugged in one of the MP's internal bays?
For the same card, No. But you will get into issues with the PCIe lane count (i.e. 1x lanes, and PCIe spec. 1.0 = 250MB/s per lane). But it's still 250MB/s, which is the limit of PM chips, and more than enough for mechanical drives.

SSD OTOH, is worth finding a SATA 3.0 model (6.0Gb/s), and it will use additional lanes as well, and likely be capable of running PCIe spec. 2.0 (500MB/s per lane). Much better for SSD use. There's just no internal port versions AFAIK that will work under OS X.

There are other cards with more lanes (i.e. 4x port models, but are substantially more expensive, but uses 4x lanes - still SATA II = 3.0Gb/s spec.).

It's this card: Digitus DS-30102 (http://www.digitus.info/en/products/accessories/?c=1202&p=15606)

Looks pretty much like the reference design, but who knows? :rolleyes:
Does only work with Sonnet drivers, even the drivers they offer don't work with OS 10.6.
I can't tell. Those chips are on so many different brands, makes it more difficult as well. And without the card, I've no way to even attempt to find out who actually manufactured the thing (hopefully, it has a manufacturer code). :confused:

In this entire thread I haven't seen anyone mention the "other" (http://www.softraid.com/index.html) (i.e. not Apple) software RAID.

Is it because nobody wants to pay extra for software when Apple's is "good enough"? Or is it because everyone thinks hardware RAID is the way to go?

Yes I know there are limitations. E.g. no RAID-5. But Apple's software doesn't support that either.
I've not used it, but if it does the same thing that OS X's Disk Utility does, why spend the additional money?

I'd skip it, and go for a hardware solution (which is what I do, as software isn't actually capable of operating parity based arrays, if it has the capability or not - write hole issue is left unsolved).

I haven't used Apple's RAID nor SoftRAID. I was hoping someone who has used both would chime in and report if it's "worth it". Obviously it can't be too popular or there would have already been a plethora of postings extolling its virtues.
I'm not seeing anything that's actually different (allows it to claim it's more stable, just a claim).

But I've not used it, so I can't be 100% sure, but my instincts are telling me it's a false statement these days. IIRC, someone had mentioned some time ago, that it was true under earlier systems (PPC days I think), but that's no longer the case if I'm remembering the post correctly (it's here in MR somewhere, but I can't recall where and am too lazy to search for it right now :o). ;) :p

phasion
May 21, 2010, 08:05 AM
someone mentioned that for raid0 in osx, that you need to create the array with disk utility before you install the osx.

in my case, i am using raid0 for scratch disk. so i am NOT running raid0 on my OSX OS, but instead using it as internal HDs for expandable drives.

is it possible to non-destructively make raid0 in osx without doing any harm to osx? or will i need to reformat my osx as well?

also, if i want to expand say a 2TB raid0 to a 3TB raid0 by adding an additional 1TB drive, can i just "add" it in disk utility or will i need to back up the 2TB to another drive, wipe out the raid0 to a raid0 with 3TB, finally moving data back over to the new raid 0?

strausd
May 21, 2010, 10:51 AM
also, if i want to expand say a 2TB raid0 to a 3TB raid0 by adding an additional 1TB drive, can i just "add" it in disk utility or will i need to back up the 2TB to another drive, wipe out the raid0 to a raid0 with 3TB, finally moving data back over to the new raid 0?

I'm pretty sure you're gonna have to back up the 2tb array, wipe it, create the 3tb array, then move data back.

nanofrog
May 21, 2010, 12:52 PM
someone mentioned that for raid0 in osx, that you need to create the array with disk utility before you install the osx.

in my case, i am using raid0 for scratch disk. so i am NOT running raid0 on my OSX OS, but instead using it as internal HDs for expandable drives.

is it possible to non-destructively make raid0 in osx without doing any harm to osx? or will i need to reformat my osx as well?
If you leave OS X's disk alone (stripe set is separate from the OS disk), then the OS disk will be fine. No data loss will occur.

The drives used for the stripe set however, WILL BE WIPED as a result of the initialization process.

also, if i want to expand say a 2TB raid0 to a 3TB raid0 by adding an additional 1TB drive, can i just "add" it in disk utility or will i need to back up the 2TB to another drive, wipe out the raid0 to a raid0 with 3TB, finally moving data back over to the new raid 0?
Yes, you'd have to make a full backup, add the disk and create the array (no way to do online expansion), and the data is wiped during the initialization phase (just as it is with the initial setup).

Online expansion is possible with proper RAID cards, but not usually with software based arrays (there are a few proprietary products that claim they can, such as some NAS products that are software based). But I've never seen it with OS based software RAID.

phasion
May 24, 2010, 03:02 AM
ahh i see,.

what if i have a software raid, ie raid0 that is seperate from OSX partition

and my osx gets formatted, will i lose the raid partition?
in other words if my osx non-raid HD gets corrupted, will the raid0 go down with it?

nanofrog
May 24, 2010, 02:33 PM
ahh i see,.

what if i have a software raid, ie raid0 that is seperate from OSX partition

and my osx gets formatted, will i lose the raid partition?
in other words if my osx non-raid HD gets corrupted, will the raid0 go down with it?
No.

If the OS X disk goes, the RAID will remain in tact. The reverse is the same as well; array gets wiped, the OS X disk will still be in tact, and working.

This is the biggest advantage of running a separate OS disk from the array, and why it's done. :D

A hardware implementation would be considerably more robust (i.e. can move it from system to system, capable of increased throughputs, and capable of levels not possible under OS X's Disk Utility, can be accessed via multiple OS's), but also have to pay for it. :rolleyes: :p

phasion
May 24, 2010, 10:58 PM
i see,

thanks for the help.

just tried raid0 with disk util and it worked out.

dcouzin
Jul 16, 2010, 06:05 PM
...you typically have to run enterprise HDD's rather than consumer models (which can be used in a software RAID, as the control is retained by the system rather than the card). So the recovery timings in the consumer models will work.

That said, enterprise drives are a good idea anyway, as they're rated better, and have additional sensors that prevent the heads from physically crashing into the platters.

nanofrog, this statement of yours from April prompts a related question:
Can it ever make things worse to use enterprise HDDs in RAID 0?
If the enterprise HDD quits error recovery at 7 seconds and sends a message to the (hard or soft) RAID controller to work around the error, then since the RAID 0 striping gives the controller no such ability what will it do? Will the controller message the HDD to resume recovery and will the HDD obey? What if the controller doesn't understand the (TLER) message from the HDD or ignores it? Do you recommend disabling TLER on enterprise HDDs in RAID 0? Can it always be disabled?

nanofrog
Jul 16, 2010, 09:23 PM
Can it ever make things worse to use enterprise HDDs in RAID 0?
I've never seen that particular case (error a result of enterprise disks, and consumer units would have been fine). Usually it's a disk failure, and the consumer models are more likely to go within a period of time. Plenty of proof of that, not just my observations.

The biggest issue to me, is there's no parity data to rebuild a bad sector from with a stripe set, but that's the compromise of that particular level (issue exists in either a software or hardware implementation). It's not the drives' fault, but the level selected by the user.

Personally, I usually skip over stripe sets as I need redundancy, though they do have their place. Basically low budget performance (redundancy either not required, or insufficient funds to obtain it), but can be effective if the bare minumum precaution is taken (backup system, and it's kept up with). In such a case, the compromise for that low cost is time necessary to rebuild the array when it fails.

If the enterprise HDD quits error recovery at 7 seconds and sends a message to the (hard or soft) RAID controller to work around the error, then since the RAID 0 striping gives the controller no such ability what will it do? Will the controller message the HDD to resume recovery and will the HDD obey? What if the controller doesn't understand the (TLER) message from the HDD or ignores it? Do you recommend disabling TLER on enterprise HDDs in RAID 0? Can it always be disabled?
The TLER values has to do with the disk's ability to remap a bad sector.

In the case of a single disk (0,0 settings), the disk will become unavailable if an error occurs, as it's trying to remap that bad sector. As a result, the system is temporarily unresponsive. In instances where the remap is unsuccessful (i.e. many bad sectors), you're libel to get an error message from the OS after some period of time, as the disk has yet to "recover", and become available to the system.

This is necessary, as there's no parity data in single disk operation.

In the case of a RAID set, if this method of recovery were allowed to happen, the set would also become unusable for some unknown period of time. It's different in this case, as it's expected that the array is available to multiple users and/or needs to be available as much as possible (redundancy). Think in terms of IOPS for usages like database systems.

To combat this, the enterprise disks have different settings, which allows the recovery operation time out at a set period of time (7 seconds during writes), to keep that array available. This isn't a problem as most RAID levels either use parity data, or another disk the data's duplicated on the corrupt data can be recovered from (rebuilt automatically). This is why most RAID card's won't even work with consumer disks (unstable at best).

A stripe set (RAID 0) is the bastard child of RAID, as it has no redundancy whatsoever, and why it's not used for high availability scenarios. So if you're running this level, it's expected the user realizes the limitations. You still have some ability to recover, but not endless (7 second limit, unless you adjust the values on the drives). If it goes past that time limit, the data will be corrupted. Basically, user peril/"learn the hard way" if they don't understand this limitation.

Hope this helps. :)

BTW, wiki has a page on TLER (http://en.wikipedia.org/wiki/TLER) if you want to research this in further depth. ;)

dcouzin
Jul 17, 2010, 09:38 AM
...A stripe set (RAID 0) is the bastard child of RAID, as it has no redundancy whatsoever, and why it's not used for high availability scenarios. So if you're running this level, it's expected the user realizes the limitations. You still have some ability to recover, but not endless (7 second limit, unless you adjust the values on the drives). If it goes past that time limit, the data will be corrupted. Basically, user peril/"learn the hard way" if they don't understand this limitation.

Hope this helps. :)

BTW, wiki has a page on TLER (http://en.wikipedia.org/wiki/TLER) if you want to research this in further depth. ;)

Thanks nanofrog for jumping back into the strand. Actually your statement quoted above does imply that the enterprise class hard drive with its 7 second limited error correction will, in terms of error correction, be worse than the desktop class hard drive for RAID 0.

I had studied the Wikipedia page on TLER and also a Samsung page on their CCLR (http://www.samsung.com/global/business/hdd/learningresource/whitepapers/LearningResource_CCTL.html) but don't understand the interactions of hard drive and controller, leading to my original question.

Yes RAID 0 is a bastard, and I'm afraid statements about RAID simpliciter sometimes overlook RAID 0 and become false. A writer of the Wiki page is obviously pissed that the utility WDTLER doesn't work on the newest WD drives, so TLER can't be disabled on their new enterprise drives. He/she writes:

"...having the choice of changing the TLER option gives the user the flexibility of purchasing the high performance drives that have TLER enabled and that are designed to run in a RAID array and using them as stand-alone single drives in their desktop computers and disabling the TLER option to enable better data recovery and lower chance of corruption and drive failures."

Here the writer carefully separates having "TLER enabled" from "designed to run in a RAID array" (durability which entails higher heat, noise, and cost) of the enterprise class drive. I think RAID 0 drives want TLER disabled for exactly the same reason that a stand-alone drive does. The writer goes on to slam WD with the conclusion:

"[New enterprise] RE disks are only suitable for RAID arrays and [new desktop] Caviar are only suitable for non-RAID use."

But here I think the first word "RAID" needs to be qualified "except RAID 0", and maybe the second word "RAID" too.

My purpose for joining drives in RAID 0 is for playback of some video which will stream at about 800 Mb/s (100 MB/s). A single drive can't read fast enough. Maybe two in RAID 0 can. Maybe three. If not three, I'll quit. Samsung 1 TB hard drives here cost 45% extra for enterprise class. That's fair, but if the 7 second error correction limit can't be disabled I'll go with desktop class. Backing up is fun to do.

nanofrog
Jul 17, 2010, 09:59 PM
Thanks nanofrog for jumping back into the strand. Actually your statement quoted above does imply that the enterprise class hard drive with its 7 second limited error correction will, in terms of error correction, be worse than the desktop class hard drive for RAID 0.
:cool: NP. :)

RAID is complicated, and can get confusing rather quickly. Available online resources can be a bit too simplistic, and lead someone into trouble IMO.

At any rate, I get what you're meaning about the factory timings in the enterprise models.

But there's two aspects of information that're being missed (one is my fault :o).

You can change the timings on the enterprise disks (REx models).
Even if you don't you won't see that issue like you would with consumer models (and why I forgot to mention #1 :o). It has to do with the fact those disks are meant for the abuse RAID hands off to the disks via the additional sensors (i.e. if it senses the vibration is getting too high, it will act to prevent the heads from impacting the platter causing physical damage = bad sectors result).


I had studied the Wikipedia page on TLER and also a Samsung page on their CCLR (http://www.samsung.com/global/business/hdd/learningresource/whitepapers/LearningResource_CCTL.html) but don't understand the interactions of hard drive and controller, leading to my original question.
Understandable.

What's worse, the exact procedure/methods used internally in the disks are still somewhat proprietary (i.e. what sensor at what value will it temporarily disable the disk's operation in order to stabilize it). Yes, SATA is a specification (open standard), but what happens in the controller board's interaction with the platters, spindle motor, and stepper motor (operates the armature the heads are mounted to), can vary from drive maker to drive maker (though the basic process isn't that different between them). SATA has commands that can be sent bidirectionally (i.e. disk sends error message to the system). Think SMART data.

So long as a disk sends/receives data within the SATA IO specification, it's deemed compliant. What happens on the other side (disk controller), may fall under Intellectual Property = proprietary (Patents). Though there is a lot of commonality (basic requirements to operate the mechanics to get/transfer data), the way they do it may not be exactly the same. Same goes for platter production (density for example).

Yes RAID 0 is a bastard, and I'm afraid statements about RAID simpliciter sometimes overlook RAID 0 and become false. A writer of the Wiki page is obviously pissed that the utility WDTLER doesn't work on the newest WD drives, so TLER can't be disabled on their new enterprise drives. He/she writes:

"...having the choice of changing the TLER option gives the user the flexibility of purchasing the high performance drives that have TLER enabled and that are designed to run in a RAID array and using them as stand-alone single drives in their desktop computers and disabling the TLER option to enable better data recovery and lower chance of corruption and drive failures."

Here the writer carefully separates having "TLER enabled" from "designed to run in a RAID array" (durability which entails higher heat, noise, and cost) of the enterprise class drive. I think RAID 0 drives want TLER disabled for exactly the same reason that a stand-alone drive does. The writer goes on to slam WD with the conclusion:

"[New enterprise] RE disks are only suitable for RAID arrays and [new desktop] Caviar are only suitable for non-RAID use."

But here I think the first word "RAID" needs to be qualified "except RAID 0", and maybe the second word "RAID" too.
WD used to allow the TLER values to be adjusted in all of their disks (initially didn't have RE = RAID Edition disks for every niche, such as in the Green series). That's now changed, so only the RE series (RE4 to be a bit more specific) allow the TLER values to be adjusted by the user with the utility. The consumer models have had that ability removed. You can still do it with older drives, but no longer with anything new in this segment (standard Blue, Green or Black, or other specialty disks; anything not identified specifically REx in the model).

This has pissed some people off, but common sense should have led them to realize this "freebie" wouldn't last forever. They're after profits, and allowing this to continue on the consumer lines cut into that, as users weren't buying the RE models.

Some got burnt too, depending on what they were doing (i.e. using consumer models for a primary array).

Consumer GP disks were commonly used as primary (on-site) backups once the TLER values were adjusted, as they were suitable for that, and corporations are noticing power bills and HVAC requirements (especially during an upgrade to the existing facilities, new facilities, or a break down of existing equipment - it's expensive).

My purpose for joining drives in RAID 0 is for playback of some video which will stream at about 800 Mb/s (100 MB/s). A single drive can't read fast enough. Maybe two in RAID 0 can. Maybe three. If not three, I'll quit. Samsung 1 TB hard drives here cost 45% extra for enterprise class. That's fair, but if the 7 second error correction limit can't be disabled I'll go with desktop class. Backing up is fun to do.
2x disks will suffice for this, especially if the individual performance is at/over 100MB/s each (allows you to go past the 50% capacity mark). Think 2TB models that run at 7200rpm (greens aren't that fast).

With slower disks, it will still work, but you have to be mindful of the capacity, as data transfers slow down once you hit the inner tracks on the platters (same rotational speed, but shorter tracks = less data read/written per rotation = reduced throughput). Additional drives help with this, but it's also at additional cost.

In your case, you probably don't need to bother with enterprise grade disks (assuming you're using the SATA ports on the logic board, not a true RAID card), especially with a proper backup in place.

Yeah, it's a PITA to rebuild an array by hand off of backups, but it's an acceptable compromise to keep the costs as low as possible.

But the enterprise disks would reduce the statistics of this happening, and the values can be adjusted with the TLER Utility (not just disabled, but actually changed to other values). I know I've seen people complain this isn't possible, but it is. You just have to enter the correct command (values are contained within the command). No values, means defaults will be used.

Hope all of this helps. :)

dcouzin
Jul 18, 2010, 01:01 PM
nanofrog, your information is very useful. If the error recovery timings of Enterprise HDDs can be changed, then my worry concerning RAID 0 disappears. The Wikipedia writer doesn't believe that the new WD Enterprise drives can have their TLER settings changed by the WDTLER utility. He/she wrote:

"Western Digital now claims that using the WDTLER.EXE tool on newer drives can damage the firmware and make the disk unusable. The WDTLER.EXE tool is no longer available from Western Digital, and new disks will not be able to have the TLER setting changed. RE disks are only suitable for RAID arrays and Caviar are only suitable for non-RAID use. The utility still works for older disks."

You contradict this when you write:

"That's now changed, so only the RE series (RE4 to be a bit more specific) allow the TLER values to be adjusted by the user with the utility."

The Wikipedia page (which you originally recommended) needs your input. Incidentally, in this one place you wrote that only RE4 series drives allow the timing to be set, but elsewhere you say REx. The 1 TB Western Digital drive now available here is the RE3 WD1002FBYS. Does WDTLER work with it?

And what about Samsung Enterprise class hard drives? (Today's price here for the SpinPoint F1 HE103UJ is 74% the RE3 WD1002FBYS price.) Can the error recovery timing of the SpinPoint F1 HE103UJ be set by the user?

(I won't ask about setability on Seagate Enterprise class hard drives because they're way too expensive here, but someone else should ask about this.)

If we agree that there are uses -- single drive; RAID 0 array -- for which the factory TLER settings on Enterprise class drives are bad, then we need to find out which Enterprise class drives offer TLER setability and how.

Thanks.

Phantom Gremlin
Jul 18, 2010, 10:35 PM
All this discussion begs the question of where to buy "enterprise" disks. Even if a consumer oriented vendor like Newegg had the disks, they might well be preloaded with random firmware for various OEMs.

So, who can we trust online?

nanofrog
Jul 18, 2010, 11:47 PM
nanofrog, your information is very useful. If the error recovery timings of Enterprise HDDs can be changed, then my worry concerning RAID 0 disappears. The Wikipedia writer doesn't believe that the new WD Enterprise drives can have their TLER settings changed by the WDTLER utility. He/she wrote:

"Western Digital now claims that using the WDTLER.EXE tool on newer drives can damage the firmware and make the disk unusable. The WDTLER.EXE tool is no longer available from Western Digital, and new disks will not be able to have the TLER setting changed. RE disks are only suitable for RAID arrays and Caviar are only suitable for non-RAID use. The utility still works for older disks."

You contradict this when you write:

"That's now changed, so only the RE series (RE4 to be a bit more specific) allow the TLER values to be adjusted by the user with the utility."
The RE4 statement meant the REx drives, RE4 being the most recent so far. I can adjust those models, though as mentioned, if you're not familiar with using the WDTLER utility, you may think that it's only possible to Enable/Disable the setting, not adjust the actual settings.

I have RE3 series in my personal system, and can adjust them. The Velociraptor (300Gb) and Caviar Blacks (1TB) can as well, but they're a bit over a year old now (model released before the RE4-GP model).

The Wikipedia page (which you originally recommended) needs your input. Incidentally, in this one place you wrote that only RE4 series drives allow the timing to be set, but elsewhere you say REx. The 1 TB Western Digital drive now available here is the RE3 WD1002FBYS. Does WDTLER work with it?
Sorry about the confusion, so see above (REx through RE4, which is the current revision number, is what I was trying to get across to you).

And what about Samsung Enterprise class hard drives? (Today's price here for the SpinPoint F1 HE103UJ is 74% the RE3 WD1002FBYS price.) Can the error recovery timing of the SpinPoint F1 HE103UJ be set by the user?
I don't deal with Samsung disks, as their consumer disks suck. To me, that's an indication of the enterprise models as well. I have the same opinion of Hitachi. But the variance between model years is enough that one bad year or so may be followed with a really good one or two. Hard to say, but I then look at warranty periods, and WD's still offering 5yrs on their enterprise disks, which makes me less hesitant (easy to get a replacement in the US if something does go wrong, as I have had to do it not that long ago, and it was an enterprise disk, but the only one out of many in the last couple of years or so).

Nor have I ever seen or heard of such a tool for Samsung or Hitachi's products. If it exists, it's kept internally within the respective company.

(I won't ask about setability on Seagate Enterprise class hard drives because they're way too expensive here, but someone else should ask about this.)

If we agree that there are uses -- single drive; RAID 0 array -- for which the factory TLER settings on Enterprise class drives are bad, then we need to find out which Enterprise class drives offer TLER setability and how.
AFAIK, Western Digital is the only disk maker to offer such a utility. I know for certain Seagate doesn't do this (only works with the card maker), which means either a card or disk firmware upgrade is offered, if anything. It's the same for Samsung and Hitachi (internal, and they release a new firmware if anything, as the card maker is more likely to make an adjustment to their firmware or just state whatever P/N is incompatible with their product).

Even if a consumer oriented vendor like Newegg had the disks, they might well be preloaded with random firmware for various OEMs.
Look for WD, Seagate, .... OEM disks, not from sources like HP,... (system vendors), that may have a specific firmware revision that's meant to work with their offered card/s.

So far, I've not had any issues from newegg, or other vendors this way (provantage does offer HP for example), but also OEM disks with the drive makers' names on the disks. Most of the time, the vendor labeled disks aren't an issue either, particularly HP (usually SAS models, as you can find on provantage.com). But it is possible, and best to avoid them if you're uncertain.

Shouldn't be a problem if you pay attention to the details. ;) If you're not sure, ask. If I don't see it, someone is surely willing to help, as that's what a forum is for. :D

Hope this helps. :)

strausd
Jul 19, 2010, 12:04 PM
How reliable would a RAID 0 be in use for time machine?

nanofrog
Jul 19, 2010, 12:27 PM
How reliable would a RAID 0 be in use for time machine?
Well, it's not used as often as a primary array which lowers it's frequency of failure a bit (assuming the spin-up doesn't go awry, as this array is usually spun down). Personally, I still wouldn't trust it. Especially if the primary is a stripe set as well (increases the chance that both arrays fail simultaneously = data is DOA).

JBOD is a better implementation IMO (can be done with no additional cost just by configuring existing disks), as worst case, you only loose the data on the failed disk, not all of it (assumes the primary source is also gone when a disk fails in the JBOD).

If your data is super critical, you'd want to consider other levels for both a primary and backup array. Which level however, would depend on specific details.

dcouzin
Jul 19, 2010, 02:52 PM
Contradictions fly around this topic. Anonymous (and undated) Wikipedia TLER writer says new WD Enterprise drives will not be able to have the TLER setting changed. A WD Knowledge Base page (http://wdc.custhelp.com/cgi-bin/wdc.cfg/php/enduser/std_adp.php?p_faqid=1478&p_created=1161619255&p_sid=FziH_g5k&p_accessibility=0&p_redirect=&p_srch=1&p_lva=&p_sp=cF9zcmNoPTEmcF9zb3J0X2J5PSZwX2dyaWRzb3J0PSZwX3Jvd19jbnQ9MiwyJnBfcHJvZHM9MjI3LDI4MyZwX2NhdHM9JnB fcHY9Mi4yODMmcF9jdj0mcF9wYWdlPTEmcF9zZWFyY2hfdGV4dD13ZHRsZXI!&p_li=&p_topview=1) says the TLER feature on Western Digital RAID Edition SATA hard drives cannot be disabled. nanofrog says he can adjust the TLER setting on his WD RE4 drives.
[added 4 hrs later: The RE4 is an attractive drive with its 64 MB cache and low power consumption. Can the TLER firmware setting on currently produced RE4's be adjusted with WDTLER?] There's internet buzz over exactly when in 2010 WD made it impossible to use WDTLER to modify the firmware in their RE drives. This is a rumor forum too.

I don't think disabling TLER is fundamentally different from adjusting its times to 0, which codes infinite time or maybe 200,000 milliseconds if the drive itself has some such limit.

There's no agreement over whether TLER enabled (set to 7 sec) is bad for drives in RAID 0. I think it is bad. I think the RAID 0 error correction strategy should mimic the single drive's. But there's no agreement over the single drive either. The anonymous Wikipedia TLER writer says that for single drives "disabling the TLER option [enables] better data recovery and lower chance of corruption and drive failures." Another WD Knowledge Base page (http://wdc.custhelp.com/cgi-bin/wdc.cfg/php/enduser/std_adp.php?p_faqid=1397) says that "a drive with TLER enabled will work with no performance decrease when used in non-RAID environments."

I don't deal with Samsung disks, as their consumer disks suck. To me, that's an indication of the enterprise models as well. I have the same opinion of Hitachi. But the variance between model years is enough that one bad year or so may be followed with a really good one or two. Hard to say, but I then look at warranty periods, and WD's still offering 5yrs on their enterprise disks, which makes me less hesitant (easy to get a replacement in the US if something does go wrong, as I have had to do it not that long ago, and it was an enterprise disk, but the only one out of many in the last couple of years or so).
For what it's worth, Samsung Enterprise drives (including the inexpensive HE103UJ) have 7 year warranty.

strausd
Jul 19, 2010, 03:16 PM
Well, it's not used as often as a primary array which lowers it's frequency of failure a bit (assuming the spin-up doesn't go awry, as this array is usually spun down). Personally, I still wouldn't trust it. Especially if the primary is a stripe set as well (increases the chance that both arrays fail simultaneously = data is DOA).

JBOD is a better implementation IMO (can be done with no additional cost just by configuring existing disks), as worst case, you only loose the data on the failed disk, not all of it (assumes the primary source is also gone when a disk fails in the JBOD).

If your data is super critical, you'd want to consider other levels for both a primary and backup array. Which level however, would depend on specific details.

How would I be able to use Time Machine to backup to two separate 2TB drives?

nanofrog
Jul 19, 2010, 05:14 PM
How would I be able to use Time Machine to backup to two separate 2TB drives?
You'll have to decide how to break the data up, but once you decide this, tell the software (folders, files) what to backup where (disk, even a specific location on it if you wish).

Loa
Jul 19, 2010, 07:39 PM
How would I be able to use Time Machine to backup to two separate 2TB drives?

I'd suggest Carbon Copy Cloner for this. It's not as pretty as Time Machine, but it's a hell of a lot easier to configure it as *you* want it to work.

Loa

DoFoT9
Jul 19, 2010, 07:50 PM
after length conversations with nanofrog and a few other members, i eventually went for a RAID1 2x2TB array (total of 2TB) which i use for backing up and my movies etc. this is attached via fw800 to my iMac i7 and easily hits 75MB/s (interface is the limitation here).

when transferring at this 75MB/s threshold it uses not even 10% CPU on my i7 imac.

hope this helps - will you go with hardware or software RAIDs?

strausd
Jul 21, 2010, 03:30 AM
after length conversations with nanofrog and a few other members, i eventually went for a RAID1 2x2TB array (total of 2TB) which i use for backing up and my movies etc. this is attached via fw800 to my iMac i7 and easily hits 75MB/s (interface is the limitation here).

when transferring at this 75MB/s threshold it uses not even 10% CPU on my i7 imac.

hope this helps - will you go with hardware or software RAIDs?

Well I have been talking to nanofrog on a different thread about putting two drives in an empty 2009 optical bay and I have gotten some great suggestions. Since the 2009 model only has one other SATA port, I would need some sort of PCI controller. There are some that are rather cheap, but I'm not sure how reliable those would be. Also, there are some that will do RAID 0 for fairly cheap too.

I'm still not entirely sure. I wish there was some way to tell time machine that if backup disk number 1 is full, then start putting backups on disk 2 or something like that. Maybe I will go check on the OS X forums.

I would love to have a RAID 0 config for storing all my stuff and use TM to back it up, that would be my ideal situation. But currently, I am still undecided on whether or not to go with a hardware or software RAID. It will probably depend on what drives I can get in the optical bay and what PCI controller I will have.

nanofrog
Jul 21, 2010, 12:26 PM
...I would need some sort of PCI controller...
No, you need PCIe, which is short for PCI Express. That lower case e is important, as it's a different slot, and won't work with PCI cards.

A software RAID is fine for a stripe set, as it's a small load on the system's resources. A true hardware RAID card would start at ~$300 USD, not what you're looking at.

And BTW, Highpoint isn't the best company to deal with, as they don't design or manufacture anything. Their support sucks as a result. I'd stay away from anything but the RR43xx series, and only use it if you don't need it to boot EFI, and know what you're doing.

DoFoT9
Jul 22, 2010, 04:53 AM
I would love to have a RAID 0 config for storing all my stuff and use TM to back it up, that would be my ideal situation. But currently, I am still undecided on whether or not to go with a hardware or software RAID. It will probably depend on what drives I can get in the optical bay and what PCI controller I will have.

given the amount of CPU usage i have experienced, i recommend saving yourself the money and build a RAID0 via software. :) im not sure on the prices of PCIe SATA controllers - i dont expect TOO much though