SAS Drive (non-RAID) vs SATA for home system?

[greggm2000]

I'm contemplating a new build, and as part of that, I see that SAS drives and controllers have become cheap enough to be an interesting solution for my needs.

My thought is to have a very fast drive for windows + installed apps, and SATA for everything else. Sure, I could go with a WD Raptor, but that's only 10K RPM, and the SAS drive I'm looking at is a Fujitsu drive at 15K RPM. I'd attach that to a Promise TX4650 PCI-E controller for a total cost of about $300 (Newegg). I wouldn't be running RAID.

My question is, is it worth it? I can't find benchmarks anywhere for this kind of scenario. Still, I can't be the only one that's thought of this. If anyone could point me to some relevant data to help me make my decision, I'd appreciate it. If you have personal experience with this, I'd like to hear your opinions.

For me, if I could get up to a sustained throughput of 100 MBytes/second, it gets interesting. If I can do 200MBytes/sec sustained, then that interests me very very much!

Thanks!

 

[MerlinRML]

The fastest SATA drives I've used have a sustained throughput of about 105MB/sec for sequential writes at the outer tracks of the disk.

The fastest SAS drives I've used have a throughput of about 115MB/sec for sequential writes on the outer tracks of the disk.

So in terms of sequential throughput, SAS is not going to give you rediculous amounts more throughput. However, the true benefit of SAS in a single user office-type of environment comes from its low access times. Jumping around on the disk as you launch an application, then open a document, while you've got music playing in the background, and you've got a DVD burning should not bog your whole system down as much with a SAS drive as it would with SATA.

The Raptors offer a similar benefit. They are no longer the king of throughput, but their higher rotational speed still provides for slightly lower access times than your standard 7200RPM disks. So in terms of day-to-day disk access, they are still slightly faster.

Really it depends on what you are doing with the disk to figure out if it will be of a benefit to you.

 

[lopri]

Agree with Merlin. If I could add to it, the sustained throughput can also be bound by the disk controller as well. In the end, it's about how far you would go to achieve additional performance. Some will say it's worthwhile but others will disagree. And remember that the benefit will also heavily depend on your usage pattern.

 

[imported_wired247]

If you are willing to spend the money on 15krpm drives and a SAS controller, then I would recommend entertaining the idea of a very impressive RAID 5 setup with perpendicular recording 7200rpm drives instead. That's basically the route I took when I was looking at SAS drives myself, and I'm quite pleased with the results, (although I can now wait for people to jump in and tell me how little difference RAID makes for the home user...)

 

[GarfieldtheCat]

Originally posted by: greggm2000
I'm contemplating a new build, and as part of that, I see that SAS drives and controllers have become cheap enough to be an interesting solution for my needs.

My thought is to have a very fast drive for windows + installed apps, and SATA for everything else. Sure, I could go with a WD Raptor, but that's only 10K RPM, and the SAS drive I'm looking at is a Fujitsu drive at 15K RPM. I'd attach that to a Promise TX4650 PCI-E controller for a total cost of about $300 (Newegg). I wouldn't be running RAID.

My question is, is it worth it? I can't find benchmarks anywhere for this kind of scenario. Still, I can't be the only one that's thought of this. If anyone could point me to some relevant data to help me make my decision, I'd appreciate it. If you have personal experience with this, I'd like to hear your opinions.

For me, if I could get up to a sustained throughput of 100 MBytes/second, it gets interesting. If I can do 200MBytes/sec sustained, then that interests me very very much!

Thanks!

IMO, it's not worth it. SATA drives are pretty fast now anyways, with high STR and 16/32Meg caches. The SAS (or older SCSI) drives are hotter and draw more power (and usually louder), and are almost always optimized for server usage, NOT for single users.

Look at thsi comparision of drives from SR

I've included the 7K1000, the fasted SATA drive in their database, but the new Samsung F!'s and WD 640Gig drives should be a bit faster then the 7k1000. I also included the two recent 15K cheetah's, and their newest SAS 10K drive.

Look at the single user benchmarks, and see that the SATA drives wins 3 out of the 5, and the other two are what, like ~10%?.

Also notice the older 15K drive is faster then the newer one, and both are way faster the the 10K SAS (yes, I know there is a RPM difference). The SAS drive gets killed by the SATA drive as well.

Newer drives perform worse for single users, as the firmware gets optimized for multi-user server usage.

 

[Rubycon]

It really depends on your usage patterns. On a more midrange system I've compared workstation boards running Dual Xeon 5460, 64GB RAM, Areca ARC 1680 SAS and six Fujitsu MAX146 SAS drives in RAID0 with 64KB stripe size.

In Vista Enterprise x64 this setup is directly swappable with the ARC-1681ML (SATA) without any reconfiguration! So 10 raptors were set on this host and striped with 64KB stripes too.

The IOP (card cpu) on the 1680 is running at 1200MHz vs. 800MHz for the 1281 so that may give a slight advantage along with the 15k rotation speed of the spindles.

The DVD shrink test - ripping an ISO of a movie to a DVD folder on the same volume is nearly identical for both set ups. (29 seconds)

The SAS volume does open big programs like Premiere CS3 faster than the 10k array. Benchmarks within the cache (2GB on both controllers) are very similar with the 1680 coming in slightly faster - due to the 400MHz advantage its IOP has.

If you're gaming, surfing, cracking, porn dipping, benchmarking, etc. then this is definitely a big waste IMO. It's like buying a big rig to drive around town. Then again I see people doing that too! Text

 

[imported_wired247]

So Ruby, what made you go with the fujitsu drives ? What do they help you accomplish?

 

[Rubycon]

Originally posted by: wired247
So Ruby, what made you go with the fujitsu drives ? What do they help you accomplish?

Best random read/write throughput. Since the controllers are similar it was a good comparison. The 1680 was supposed to have an 800MHz IOP but it's one of the brand new ones with a 1.2GHz cpu. Not that I am complaining but that was a surprise. I want to try MBA's as they double the areal density of the MAX increasing the STR another 25 or so MB/S on outer tracks. Since it's a newer generation they'll probably perform slightly better too. 300GB with four platters (vs. 146) at 15K will be nice. Ironically the MAX drives run 1-2 degrees hotter than the raptors in the same backplanes with identical airflow. Of course loading the system up getting those actuators rattling like the rearview of a truck at a db drag - makes temperatures increase higher and this is witnessed along with the backplane fans speeding up slightly higher.

What I really want is SAS SSD's in 2.5" format. I have a mobile rack that takes four drives and is the size of a CD rom! Four drives in a single 5 1/4" bay is insane!

 

[GarfieldtheCat]

Just curious, what do you use that array for?

 

[Rubycon]

NLE scratch data.

 

[imported_wired247]

Originally posted by: Rubycon
NLE scratch data.

Do you work for TV or hollywood or something? Just curious. Or is your rig for purely freelance purposes

and what software? Avid?

 

[Rubycon]

Originally posted by: wired247

Originally posted by: Rubycon
NLE scratch data.

Do you work for TV or hollywood or something? Just curious. Or is your rig for purely freelance purposes

and what software? Avid?

Local production use only - Jean Ann Ryan Productions. All sorts of software/console mapping/management runs on the box. Avid, After Effects, Premiere, etc.