Understanding RAID options with the MacPro

Apple's RAID card is proprietary garbage. It only works with the internal SATA backplane, which would limit you to 4 internal drives on the RAID. I would check out Atto and Areca as alternatives.

With software RAID in Mac OS, you'd be limited to RAID levels 0 (striping), 1 mirroring and 10 (stripe + mirror hybrid). A hardware RAID card would also allow RAID levels 3/4/5/6 and its derivatives. Additionally, RAID cards have dedicated processors, cache memory and in some cases, backup batteries. All of these things lend to greater performance and reliability versus software RAID setups.

With 2009-10 Mac Pros, you would have to run physical cables to the internal drives when using a 3rd party RAID card. This would also require modified drive sleds that prevent the drives from attaching to the existing SATA backplane, like these.

I'm pretty sure that all of Atto's cards that support external connections use mini-SAS (serial-attached SCSI) ports, whereas Areca does make RAID cards with eSATA ports.

This is probably something nanofrog could answer. I've never attempted to boot Win 7 over Bootcamp on a hardware RAID. Though it seems like it would be a lot simpler just to dedicate a single drive separate from the RAID to Windows. Obviously, Windows needs an NTFS partition, whereas Mac OS needs HFS+.

 

I got the 6-core 2010 macpro, would the following setup work:

disk1: osx disk, 80gb ssd in lower optical bay
disks 2&3: 2x1tb wd black in software raid0, in disk slots 1&2
disk4: 1tb bootcamp drive, in disk slot 3
disk5: 2tb backup drive, having it take time machine backups of disk1 + critical parts of other disks

I vaguely remember reading from somewhere that boot camp won't work with software raid setups, but would it work in the layout i listed above? the bootcamp drive itself wouldnt be in raid. Heeeeeeeelp!

 

To extend that question a bit further, would it help if the bootcamp disk and the raid0 setup switched places, so that the boodcamp disk is before the raid0?

 

What model MP do you have?

In the recent past, I've gone with using a separate controller for a Windows disk when there was a RAID set created under Disk Utility (all disks expected to be connected to the system's SATA ports, as Disk Utility had made changes that would prevent a Windows disk from booting). There will still be cases that this is needed (more disks than ports available on the ICH).

This seems not to be the case for the 2009 systems or 2010's from information posted by Transporteur, and I trust the information given (2008 systems for sure = won't work, as it was tested out in every possible configuration; assuming there's sufficient ports for the the disk count).

 

just bought a mac pro for my wife who is seriously into photography. plans are

inside:
240 GB SSD boot/apps/bootcamp partition for windows
4 x 2TB partitioned into
a small (~50GB per disk?) RAID0 stripe scratch for photoshop etc striped across 4 drives
and ~4TB main volume using balance of space with RAID1 mirror (using SoftRAID)

then with an external esata enclosure - 3 disks for nightly clones of the SSD and the main volume, a time machine disk and a big windows volume.

 

a thought the sratch on the same spindle as your storage is slower !
and doing partitions and the same spindles is even slower another small step ?
now with 4 across ? you might break even doing some PS tasks but when it comes to the writing a large file back to the disc you will get hit having them on the same spindle !!!
you can read some who disagree but even digiLloyd now says two SSD are quicker !!!! than his 4 disc raid 0 was ?

things change and a lot of people on the interwrong dont test they pass on info

I have done massive testing ? but I also say dont even believe me take what I say and other and find a common point and do your own testing with your own files and machine its the only way to really get the fastest setup
and people like me who do this for a living and Lloyd etc.. and some here can get you closer to the starting point of testing !



if you are putting that much into it ? I would say/ask what amount of memory ?

and pull the DVD burner out stick it in a external and then throw in a cheap 40 gig SSD for PS scratch ? while it might die soon some say ? but who knows at $99 if it last a year ? warranty it ?


if you dont go that route
I would setup those 4 discs as raid 1/0 (1+0) and just put/point the scratch on the same volume and let PS write the scratch as it goes ? in my testing this has been quicker than a separate partition on the same spindle !!! notice the same spindle !!!!

having PS scratch on a separate is always going to be better option


check out this link
http://macperformanceguide.com/OptimizingPhotoshop-SSD.html

 

Appreciate everyone's advice - this site and diglloyd and bare feats have helped a lot. I've read some mixed reviews of using software RAID using Apple's disk utility and SoftRAID can't do RAID 1+0. diglloyd's tests showed 4 drive stripe on mechanical drives a bit worse but still in ballpark of raid 0 stripe of 2 SSD's . I may try just keeping PS scratch on the SSD or on one of the mirrors - Ive got 48GB RAM and I've read PS does good job of using any extra RAM to cache scratch.

 

Well, isn't hourly Time Machine-backup enough?

 

no time machine is not enough if you really need the data.

 

Wanna give an example why?

 

Thanks for the reply!
I have the mid2010 6-core. So what I was planning to do 'should' work on this machine?

 

it cant do 1/0 anymore ? I would say try it ?

create two raid 1 then drag those into a raid 0

while I prefer hard card ? it used to work well when cards were tough to get that were quality

 

You don't want to use a stripe set as a backup for another stripe set IMO assuming this is what you mean to do (risk for failure = failure of a single disk * n disks, so the risk is higher than that of a single disk). Not good, as the data would seemingly be too important to be lost.

You'd be better off using 4x disks internally in a RAID 10 configuration, and go external for backups and a separate stripe set dedicated for scratch. Keep the SSD internal in the empty optical bay.

 

I had dinner tonight with a buddy who is an engineer at apple in cupertino

I told him how I wanted to set up my rig,

ssd in optical bay for osx
hhd1 - 1tb, windows7
hhd2,3,4 - 3x2tb in raid 0, data
Backup - Qx2 8tb raid 5
Backup 2 - Drobo (offsite)

I mentioned to him about the problems people are having with windows7 and raid. He said as long as the windows7 install isn't on one of the disk in the raid array then there shouldn't be a problem.

I am still on the fence though

I may do an install like the mpg photo workstation where it's 2 drives in raid 0 and two in raid 1 for time machine, and not install windows at all.

 

Time machine is an effective backup; if you need the data immediately, you shouldn't be looking at backups and more at expanding your storage capacity.

 

the obvious reason is if your system fails along with the time machine you are sugar out of luck. if you really need info. you have to have at least two completely different backups.

if you do hourly time machine as your backup and the hdds the time machine backs up have been corrupted by spyware and / or virius then your time machine backup will be bad.

if you do time machine as your backup 1.

and if you clone your data with a cloner like superduper and physically remove the clones from the site you will be far less likely to lose data that cannot be replaced. if you have an off site place with 3 backups and rotate them once a week bring one of the backups to your mac pro and clone the info. along with the time machine that stays in place with the mac pro. your data will be far safer then just banking on a timemachine .

this backup plan is in context with my statement that it is data you really need and can't lose. Not photos of your family reunion or a trip to a zoo with your wife and kids. but photos/videos of a wedding you were paid a few k to shoot.

 

Apple's disk utility raid can do 1+0 but SoftRAID does either raid 0 or raid 1 (you can mix these though in separate partitions on the same physical drive)

SoftRAID sounds pretty robust and company seems pretty on top of things technically so going to give that a try first - would rather avoid extra hardware - I see it as another potential point of failure and don't want to worry about finding replacement card years down the road.

was reading that unlike hardware based raid 1 mirror it can do multithreaded reads off mirrors along lines of striped performance - good writeup here:

http://p2pro.com/node/21/function.include

 

TimeMachine won't boot. A clone backup will. Time Machine for incremental and clone for bootable.

 

I was just pointing out what you said

I just said try it ? I guess when I first read it sounds like apple and softraid cant do 1/0
now if I re read I guess its like apples has issues and softraid cant do 1/0 ?

wasnt sure heheheh



in the past softraid was not on top of things so will never use them again !
I think it was on the update to tiger or leopard one of those cats they were late with updates and it did not work ? no biggy as I just used backup but they took to long to get things working so decided it was not worth it and wont go back to them again ?
and decided using someones SOFTWARE to do raid and since apple does a good job and its built in ? never again ! and quite a few people got hosed !


I have never had issues with built in apple raid when I used it for 1/0 ?
I still use it for 0 and for 1 on their own
in the past areca did not have support for apple so it was highpoint which sucked ! when areca came out with cards things were back to hardware raid !

once you use hardware raid cards and not what I call soft cards ! you will understand why they are superior ? if anything the failure point is strengthened in some aspects and getting cards down the way ? not a big deal like a computer you move on to new stuff and move old data over etc..
at almost 50 years old I have been around the industry a long time

so i speak of softraid from past experience ? I speak of hardware raid from experience and using apples from experience ? the only thing I ever had issues with are cards from Highpoint !! and softraid

 

that is another good example. also having an osx clone is good if you did a software upgrade to your in the mp hdd osx and don't like what the software did. you can go back to a clone say 10.6.3 vs 10.6.4

hdds are cheap if have 4 or 5 laying around like cassette tapes or vcr tapes it is not costly. i have modded macminis for the last two years. I always have 5 to 10 2.5inch hdds that were pulls from the minis. i put them in sleds from velocioraptors and use them as osx only backups. cost is really cheap. a 160gb hdd pull from a mini is worth 30 to 40 bucks tops if I sell one on ebay. I clear under 30 bucks after fees and shipping so I have them laying around for osx backups.

 

1+0 is safer than 0+1 anyway, and why I presume 0+1 isn't allowed by Disk Utility. So I don't see any need for SoftRAID at all.

I don't trust much from Highpoint, as they don't design or manufacture their products. The RR43xx series is made by Areca, but it's difficult to get the EFI firmware out of them.

As per Areca and OS X, they only had to develop the drivers, as EFI was required for Itanium systems (which you will find with their products as well as ATTO's). I guess they waited to see if developing the OS X drivers was financially viable (large enough market) before proceeding. No way to be sure though (may have had difficulties with the early driver development due to a lack of familiarity, though I'd think their Linux development experience would have negated that substantially).

Exactly. Hardware RAID is definitely worth the cost involved, and most of it can be transferred from one system to another long enough to make the costs much easier to absorb (card + cables + enclosures). Drives die and capacity and/or performance needs mean they get replaced (typically a 3 year MTBR anyway).

Even more important to have lying around when using RAID as well, as there are occasions where OS Updates can cause issues with arrays (Software or Hardware). Which means you have to roll the OS version back, and a clone is the fastest way to do that.

And as you say, HDDs for this don't have to be big, and can be had cheaply (especially when compared to what a user's time is worth when the system is used to earn a living).

 

I think you and I think a lot alike ?

whats funny is you see a lot of people saying 0/1 (0+1) and try to tell them no do the opposite and they tell you its the same

shaking head walking away from those types hehehheheeh

 

All you can do is explain it the best way you can. If they don't understand it or won't heed the advice, there's nothing more you can do.