[damiensmunki]

Hi, guys... I bought and installed a 10K RPM 1.5Gb/s Raptor a few days ago believing it was the fastest single SATA drive available. Today, I noticed a 500 GB 7200 RPM Seagate with a transfer rate of 3Gb/s. Can you guys shed some light on which of these will be faster in general everyday use (games, photo editing, internet, etc.)? I will use one of these as my system drive with a 500 GB data drive (already own), and a 250 GB drive with a Windows partition, and a system backup partition. Oh...and it's in a Mac Pro. Thanks!
Rob

[OreoCookie]

These are just the speeds of the interfaces which have zero to do with the actual performance of the respective harddrive.

[damiensmunki]

So the Raptor is still the fastest game in town?

[bowwowman]

Originally Posted by damiensmunki 

So the Raptor is still the fastest game in town?

in terms of sheer, raw speed, yes

although the newest generation of 3gb/s drives are coming closer & closer to them. And the MP supports 3gb/s, so if the Raptors are still at 1.5gb/s, it wont be long before they are passed up performance wise

[damiensmunki]

Hmmm... So which would you guys pick? The Seagate is about $50 cheaper.

[OreoCookie]

Theses drives have nothing in common other than being harddrives. One is a sportscar, the other a four-door sedan. If all you do is what you claim you want to do, you won't benefit from the Raptor other than bragging rights.

[mduell]

SATA 1.5Gb/s tops out (on paper, and pretty close in reality) at 150MBps; SATA 3.0Gb/s brings that to 300MBps.

The 150G Raptor and the 1TB drives top out around 90MBps, and most 500/750G drives top out around 80MBps (I've heard the new Seagate 1TB tops out a tad over 100MBps, but I haven't seen the source). So the SATA 1.5Gb/s bus isn't a limitation yet.

[svtcontour]

Transfer rates actually mean little in real world performance. For that faster access times matters.

I must admit though, the raptor even though on paper it looks strong, does not seem to make nearly the impact that a 10K SCSI makes so I think the interface also has a lot to contribute. I have a raptor in one of my dual core boxes and it doesnt feel as good as an old Quantum Atlas 10K drive on a U2W controller. Benchmarks better and faster but using the computer, the older SCSI stuff still feels more responsive.

[mduell]

Does your motherboard support NCQ? That could be why the Raptor isn't as fast as it could be in your system.

[OreoCookie]

That's very surprising. The Raptor's through-put is definitely faster than on early SCSI 10k drives. The interface shouldn't matter either, as long as it is fast enough for the drive (which in both cases it is). The SCSI 10k drive (if it's old) has a much lower data density on the platters. As a matter of fact, the Raptor's maximum throughput is higher than the total bandwidth of U2W SCSI (80 MB/s if memory serves me right).

I would also think that either something is wrong with your system or that you simply don't use the same workload.

[Phuncz]

People think that more RPM means more speed. Everyone already knows that more horsepower on a car doesn't mean it's faster. The Raptor is the same story.
The following data is taken from the storagereview.com website which measures real performance and not brochure performance.

The Raptor 74GB and 150GB drives use 10.000rpm with 16MB of cache. It has S-ATA 150 (1.5Gbit per second).

Average random seek time:
8.0ms (for 74GB)
7.7ms (for 150GB)

Throughput read speed:
72MB/s (for 74GB)
88MB/s (for 150GB)

Compared to a 500GB Hitachi and 1000GB Hitachi, with S-ATA 300 and with 16 and 32MB cache respectively.

Average random seek time:
13ms (500GB)
13ms (1000GB)

Throughput read speed:
77MB/s (500GB)
87MB/s (1000GB)

So what this teaches us ? That the transferrate isn't better at all in practice. Although the 36GB Raptor drives are a lot slower in transfer speed, the new drives with 16MB cache are on par. No, what makes the Raptor drives special is this:
- unmatched seek time in contrast to 7200rpm drives which results in a more responsive desktop system. Also helps with lots of small files/scattered fragments.
- unmatched reliability due to special technology and components to ensure a much longer life (higher MTBF).
- superior robustness in RAID arrays and large server setups due to special technology
- on-par transfer speed to 7200rpm drives

What the Raptor drive isn't:
- fastest drive bar none
- best drive for high transfer speeds
- best drive for small RAID 0 arrays

It's quite simple: if you use Photoshop with lots of large files, you typically want a high transfer rate. Raptor drives in RAID 0 is cool but it isn't a requirement. The WD Caviar SE16 750GB is about the fastest S-ATA drive when you require transfer rate. Two of these in RAID 0 gives you almost 200MB/s transfer rate (max), which is a little more than 180MB/sec that two Raptor 150GB drives would give you. And here is the difficult part: will you go for storage capacity or for reliability and low seek times ? It depends on what your other needs are.

If you use your Mac Pro as a high-end all-round computer, you're better of with a low seek time, because of the many files for the OS, internet cache, games, etc. Thus the Raptor drives prove to be the better choice. Than again, it also matters a lot how you setup the storage. For high-end all-round computing, the best scenario (price/perfomance wise) would be a 150GB drive for the OS and games/programs, a seperate 150GB drive for the swap and scratch file and two seperate storage drives (500 to 1000GB typically) that are both identical (using RAID 1 or scheduled copy software). Putting the Raptor drives in RAID 0 doesn't make your system faster at all because you are putting the swap and scratch files on the same disks, which means a lot more activity on the heads.

[mduell]

Originally Posted by Phuncz 

The Raptor 74GB and 150GB drives use 10.000rpm with 16MB of cache. It has S-ATA 150 (1.5Gbit per second).

Throughput read speed:
72MB/s (for 74GB)
88MB/s (for 150GB)

Compared to a 500GB Hitachi and 1000GB Hitachi, with S-ATA 300 and with 16 and 32MB cache respectively.

Throughput read speed:
77MB/s (500GB)
87MB/s (1000GB)

Which is great, when the drive is empty. What happens when it's almost full?

150G Raptor: 60MBps
500G Hitachi: 42MBps
1000G Hitachi: 46MBps

The Raptor's performance is more consistent across the entire disk.

[OreoCookie]

He still has a very valid point: you will benefit the most from a Raptor when you need fast access times. (Or bragging rights )

[svtcontour]

Originally Posted by mduell 

Does your motherboard support NCQ? That could be why the Raptor isn't as fast as it could be in your system.

Ya the raptor is on a Core2 system with an Asus P5B-E system which has the ICH8R chipset and NCQ is enable in the BIOS (set to AHCI which enables it).

The raptor does benchmark faster in transfer rates compared to the much older Atlas 10K but slower on access time. I'm sure copying a large stream of data will be faster but dealing with many small files will be faster with a drive that has a faster access time. Also NCQ on the raptor will be far behind NCQ on a SCSI drive. Thats why as queue depts increase, SATA drives with NCQ enabled start to trail fairly badly.

My main box has a pair of 15K U320 Fujitsu drives on a dual channel U160 controller and I can say that this setup makes my box with the raptor feel like molasses. This might be understandable though.

On a note, enabling NCQ on the raptor knocks the average transfer rate from 73mb/sec to 62mb/sec. The average transfer rate for the Atlas was in the low 50's. Average access time of the raptor with NCQ was 8.2ms and average access time of the Atlas was 7.6ms

[reRESERVEDFX]

There actually IS an ability to run with such an incredible speeds. The only thing you need to do is set up a RAID 1 and you can even get a linear speed of 220MB/s

[Phuncz]

You mean RAID 0, RAID 1 is mirroring which just makes duplicates on different drives.

[CIA]

Put simply, with lots of little files, like on a boot drive then Raptors are great. Lot's of big single files (in my case, DV video) newer high capacity drives are good.

I used to boot into dual Raptor 150's in a RAID 0, and my machine was super snappy. Eventually I started to worry about data reliability, and needed more space so I switched over to a single WD 500, and while slightly slower to me, it's works fine for my needs.
Presently I have 2 Raptor 74's and 2 Raptor 150's sitting in a box un-used.

[mduell]

Some RAID1 implementations allow you to interleave reads, giving RAID0-like read performance.

[Phuncz]

Isn't that RAID 10, a RAID 1 array of two identical RAID 0 arrays ? Nasty because it costs you 4 drives with only half the capacity of the total sum. That's why there's RAID 5.

[mduell]

Originally Posted by Phuncz 

Isn't that RAID 10, a RAID 1 array of two identical RAID 0 arrays ? Nasty because it costs you 4 drives with only half the capacity of the total sum. That's why there's RAID 5.

RAID10 implementations achieve the same result, but there are some 2drive RAID1 implementations that will interleave the reads.
RAID5 is good for capacity, but the write performance blows.

[ninahagen]

The WD Caviar SE16 750GB is about the fastest S-ATA drive when you require transfer rate.

If you use your Mac Pro as a high-end all-round computer, you're better of with a low seek time, because of the many files for the OS, internet cache, games, etc. Thus the Raptor drives prove to be the better choice. Than again, it also matters a lot how you setup the storage. For high-end all-round computing, the best scenario (price/perfomance wise) would be a 150GB drive for the OS and games/programs, a seperate 150GB drive for the swap and scratch file and two seperate storage drives (500 to 1000GB typically) that are both identical (using RAID 1 or scheduled copy software). Putting the Raptor drives in RAID 0 doesn't make your system faster at all because you are putting the swap and scratch files on the same disks, which means a lot more activity on the heads.[/QUOTE]

I am really thankful for your post. That is exactly what I will do:

2 x 160 GB Raptors (1 system, 1 scratch)
2 x Large 7200rpm drive in RAID 1

3 questions:
— I do work with huge PS files in big batches. Would the new Seagate 1TB, Hitachi 1TB or the 750 caviar be better for the hi-capacity drives?
— If I want to put Windows on the System drive, should I partition it?
— Is RAID fairly safe for backing up? What are the issues? (I would use something external, but I recently felt that I just can't stand more boxes in my office... all in one is worth some limitations. Clean is good for me.

nina

[mduell]

Higher capacity drives are generally faster, but the SE16 is the fastest despite it's lower capacity.
Yea, you have to partition to run Windows on bare metal.
RAID is not a backup. In addition to the usual risk of having a drive fail, you also have the risk of the RAID controller (hardware or soft) going apeshit and corrupting your data. If you need a backup, make one; you may want to use one 750GB drive for data, and the other for backup (with a nightly copy of new/changed files, or Time Machine).

[OreoCookie]

A RAID1 is not a backup, it just protects you against drive failure, nor is simple copying. Depending on the size of your projects, work out a solution (have a look at one of your earlier threads). You should store your backups off-site and definitely not just clone drives.

Edit: mduell beat me to it.