[Laurence]

After looking at a bunch of reviews it seems like the raw data transfer of the new 1TB drives (Samsung, Seagate, Maxtor) seem to be similar to the WD Raptor, but the access time is much better for the Raptor. Does anyone think this make a large difference in the general responsiveness of the system since everything else is so fast anyway. The system in question will have 8-10 GB RAM so many things will likely be cached in RAM anyway. I'm definitely getting a few TB drives, but really need to decide whether it would be worth it to get a Raptor for the boot drive. The disadvantages I can see are really just having to setup my home directory to map to one of the other TB drives. What if I raided two TB drives in a stripe configuration, would that be better than the Raptor? Does RAID effect access time or just throughput?

[Tenacious Dyl]

I have both a WD Raptor drive and a Hitachi 1 TB drive currently in my Mac Pro. I too found that the TB drives are quite fast and ended up switching my boot drive from the Raptor over to the TB. A couple tasks were slightly (I mean slightly!) faster with the Raptor, but the TB drive is definitely holding its own. The reason for the switch was that I had almost filled the Raptor, and really didn't feel like figuring out which files to split across drives.

I use the Raptor for my bootcamp usage, and the TB for my mac usage, and things are working pretty well. If you need the space that the Raptor's can't exactly provide, I would definitely spring for the TB drives, especially as their prices are starting to become more reasonable.

Running striped RAID will affect all of your times for the better, at least in my experience. As the files accessed / copied / read are of course divided between two drives and not one, you will see a big improvement. Given how close my Raptor and TB drives are, doubtlessly if you ran two of the TB drives in a stripe array, you would have a very nice speed boost, and do better than the Raptor.

Like you said, you have a ton of RAM, you're going to get TB drives anyway, I'd just spring for four TBs and no raptors. Set up two of the TB in stripe, see how you like things, etc. Hope this helps.

[mduell]

Yes, you want a quick drive like the Raptor for your boot and scratch disks. The access time really makes a difference here as the head runs all over the disk.

RAID helps throughput but does nothing for access time.

[ninahagen]

Originally Posted by Laurence 

After looking at a bunch of reviews it seems like the raw data transfer of the new 1TB drives (Samsung, Seagate, Maxtor) seem to be similar to the WD Raptor, but the access time is much better for the Raptor. Does anyone think this make a large difference in the general responsiveness of the system since everything else is so fast anyway. The system in question will have 8-10 GB RAM so many things will likely be cached in RAM anyway. I'm definitely getting a few TB drives, but really need to decide whether it would be worth it to get a Raptor for the boot drive. The disadvantages I can see are really just having to setup my home directory to map to one of the other TB drives. What if I raided two TB drives in a stripe configuration, would that be better than the Raptor? Does RAID effect access time or just throughput?

A few observations:

— You should not RAID the system drive. If you lose a drive, you won't be able to boot easily, firmware conflicts, slowdown due to one head trying to read both system commands and the files, etc.

— Everything depends on what you are doing. For general use with light apps, the TB drives will be fine... as a prior poster said... only slight improvements with a Raptor. If you are doing any work with Photoshop, Illustrator, Aperture, Video, 3D etc, having a separate, fast system/scratch drive will make a HUGE difference, particularly when doing batch work.

— Please tell us:

> what apps you work with
> open one at a time, or all at once
> maximum file size you work with often
> files open one at a time, or multiple files at once
> current amount of data
> amount of data you expect in a year, 2 years, 3 years
> will you be using time machine

we will give you our best suggestions knowing these things.

[Night_Sailor]

For best drive performance, if you can afford it, this is what you want:

Hardware RAID and SAS drives:
Start with a set of four 300 GB SAS drives internal to the Mac Pro @ $700 each, plan on spending $3500 with spare drive for 1.2TB of storage. You need the apple Raid controller for this--another $950. Call it $4500 for all that. An after-market hardware RAID card might work--do you homework if you go that route. By the way, the APPLE hardware RAID controller card will work with the inboard eSATA drives, if you chose to go that route, according to APPLE. WARNING: Do not mix SAS and eSATA drives in the MAC PRO or in an any external enclosure--they have different vibration signatures and each can screw up the other performance.

Operating System:
There is no reason not to put the OS on a Stripe set. It will not benefit at all on boot up times, and it can be a bit of a PITA to restore. APPLE typically sets up it's systems with a separate boot drive and a stripe set. I think that is a bad idea personally--the more drives in a stripe set the better the performance. Clearly a 15,000 rpm drive will have fast performance. In a stripe set, it can't be beat.

For video these drives won't have the space of a TB eSATA drive, but they will be able to keep up, just barely with RAW HD video. A larger stripe set will have a bit more breathing room. You can shuffle data from your external eSATA RAID array to the SAS array as needed. I'd use RAID 5 but if you need more speed, you can give up redundancy and risk data lost for speed with RAID 0. Something to consider if you have the data backup elsewhere and don't mind some rework if you lose a drive.

External Enclosures:
You can back up both data and OS with an external eSATA enclosure. I've seen some cheap 1&2 bay enclosures. I've also seen cheap 12 bay enclosure that will work for larger RAID arrays that can be made to work.

Cheaper Option:
Most people don't want to spend that kind of money so they look for other compromises like a single TB drive. The problem with that is if you buy a desktop drive, it will not work well in a RAID setup and a RAID drive will not work well as a single drive. A bare minimum should be two TB RAID eSATA drives set up as a mirror. NewEgg and other places sell eSATA case brackets that will feed the two spare mother board eSATA connectors to the outside of the computer case. So you can support up to 2 TB in external eSATA with just a pair of eSATA cables and TB drives 1+1=1 1TB of back up set up in a mirror array [RAID 1].

External RAID 5:
It would not be a bad idea to hook up a few external RAID 5 arrays. Say another 20 1TB drives (two as spares at $300 each--$3000, plus a card and enclosure $400 to $700. Total for that call it $3500 for 8 TB. $7000 for 16TB. You can spend even more if you chose to use APPLE products for the external RAID array. You can go crazy and build a couple of external SAS RAID arrays for lots more money ($14000 in drives, $700 plus for enclosures) for 11.2 TB external. Now you are read to make a major motion picture.

BLURAY: Better shove a Bluray drive in there so you can dump your finished work onto disk to make space. $700

Oh, and in a few years you won't be able to sell this stuff for 1/10 of what you paid for it. So you better be able to make money with it.

[mduell]

Originally Posted by Night_Sailor 

WARNING: Do not mix SAS and eSATA drives in the MAC PRO or in an any external enclosure--they have different vibration signatures and each can screw up the other performance.

How exactly is an external eSATA drive going to shake the internal SAS drives?

Originally Posted by Night_Sailor 

It would not be a bad idea to hook up a few external RAID 5 arrays. Say another 20 1TB drives (two as spares at $300 each--$3000, plus a card and enclosure $400 to $700. Total for that call it $3500 for 8 TB. $7000 for 16TB.

Oh please show me where you can get a decent 10 port/bay RAID5 card or enclosure for $700.

[SierraDragon]

An OT question regarding external drives spinning down: With "Put the hard disk(s) to sleep when possible" unchecked under the Energy Saver internal and external drives and arrays on my MBP and G4 tower keep spinning as planned (OS 10.4.11). A friend (G5 Quad) however reports that, her (prebuilt OWC similar to mine) external FW800 RAID0 drive array routinely spins down when not being accessed. Is there another setting we are unaware of?

TIA

-Allen Wicks

[schalliol]

Originally Posted by ninahagen 

You should not RAID the system drive. If you lose a drive, you won't be able to boot easily, firmware conflicts, slowdown due to one head trying to read both system commands and the files, etc.

I disagree, a true RAID has redundancy and a RAID 1 is an ideal configuration for a startup volume, and if you use SoftRAID, you'll get faster reads than you would on a single drive. Given all the system reads you will have on a daily basis, this is an advantage. You can boot easily on just one drive if needed.

[SierraDragon]

RAID1 requires at least 2 of the 4 internal drive bays. Unless one is building extensive external drive arrays, using 2 of the 4 internal drive bays for the system is usually inappropriate. However I like the idea if I had more slots available.

-Allen Wicks

[schalliol]

Inappropriate? It seems reasonable for the speed and reliability of a critical machine to have this functionality. Hard Drives are just hard drives. If you run out of space, just drop in a PCIe eSATA card and put some in an external enclosure. I keep my main data on a NAS.

[SierraDragon]

Originally Posted by schalliol 

Inappropriate? It seems reasonable for the speed and reliability of a critical machine to have this functionality. Hard Drives are just hard drives. If you run out of space, just drop in a PCIe eSATA card and put some in an external enclosure. I keep my main data on a NAS.

Your logic is sound but NAS properly done is expensive. Without NAS, 2 bays for the OS, 3 bays for RAID0 and 1 bay for on site backup is too many bays for all internal. Reliability is irrelevant with the OS drive cloned to off site anyway, so it gets to whether RAID1 for the OS drive adds performance significantly enough to have a 2-drive RAID0 instead of 3. My guess is that for images work putting the drive in the RAID0 array is best but I honestly do not know.

Maybe you are correct and full-time external drives should be in the mix from the beginning, but that is what I am trying to get away from.

-Allen Wicks

[StrongBad]

Anyone else in awe over the prices of 1TB's lately? I just grabbed several 1TB Seagates for an amazing price:

Newegg.com - Seagate Barracuda 7200.11 ST31000340AS 1TB 7200 RPM 32MB Cache SATA-300 Hard Drive - OEM

I remember paying $500 for a 1.2 gb drive WAY back in the day. Craziness.

[mduell]

The 1TB hard drive prices are falling slowly over time... just like every hard drive before them. They still have a 25% premium over 500GB drives on the $/GB metric.