SATA or SAS?

[Idonno]

I'm thinking about buying this motherboard here:

http://www.newegg.com/Product/Product.aspx?Item=N82E16813157327

http://whatswithjeff.com/asrock-x79-extreme11-lga2011-motherboard/

http://www.asrock.com/mb/Intel/X79%20Extreme11/

http://www.servethehome.com/asrock-x79-extreme11-lsi-sas2308-onboard-sassata/

http://www.youtube.com/watch?v=aQeVjgyFdEM&list=UUK2t9Vtqq7AYKXCShevGcmA&index=2&feature=plcp

As a storage junky one of the many things I find very intriguing about this motherboard is it's 14 Sata/SAS ports and the 8 port LSI raid.

The onboard LSI raid controller has the same LSI controller chip found in mid-range LSI PCIe raid cards costing around $350 and can use either Sata or SAS hard drives.

My Intention is to build a 16TB - 8 drive redundant raid array on the 8 LSI ports. My question is which is better Sata or SAS? And why?

I have spent quite a few hours on Google and have come up short of any intelligent answers.

I get answers like: "A 15000 RPM SAS drive is faster than a 7200 rpm Sata drive."
DUH!
or
"SAS drives are for enterprise solutions so they are generally of a higher quality."
While this may be true there are many similarly priced/specced quality Sata enterprise drives so, that point is useless as well.

Some say SAS has better data integrity. Is this true? Better than a Sata enterprise solution made for raid? And if so why?

 

[4745454b]

I'd go SATA. The drives are cheaper and assuming you are a single or single digit number of users any extra speed SAS provides is wasted. Setup your RAID 5 or 10 array and be happy.

 

[Idonno]

I'd go SATA. The drives are cheaper and assuming you are a single or single digit number of users any extra speed SAS provides is wasted. Setup your RAID 5 or 10 array and be happy.

Yea, I hear what your saying about the whole cheaper thing but, I'm still interested in finding out what (if any) difference or benefits SAS offers over a similarly priced/specced enterprise Sata drive.

 

[4745454b]

To my knowledge controller and speed. SAS controllers offer more features, though perhaps not those that matter to home users. They are also usually 10K RPM or higher so they offer better access times.

 

[Idonno]

To my knowledge controller and speed. SAS controllers offer more features, though perhaps not those that matter to home users.

While that may be true, the avg home user doesn't build a 16TB raid array with enterprise quality hard drives either. I'm not your avg home user.

While raid is certainly becoming more common among home users. I doubt the avg home user builds any raid array at all. As far as the "more features" go without knowing exactly what those features are and what they do it's impossible for me to make an informed decision as to whether a SAS or an enterprise Sata drive with similar specs would be a better choice since the prices are very close.

They are also usually 10K RPM or higher so they offer better access times.

This is only true up to about 750GB but, by the time you get to the size I'm interested in (2TB possibly 3TB) all the SAS 6Gb/s are 7200rpm with the exception of a couple of IntelliPower WD's that are probably only 5400RPM or slightly better.

So again I'm still looking for actual reasons why one type (SAS 6Gb/s vs Enterprise Sata 6Gb/s W/similar prices & specs) of hard drive might be better than another for a 8 drive redundant raid array, 16TB in total size. THX

 

[4745454b]

By Avg home user I"m talking about the fact that its just you. You use a big SAS array when you have 100+ users all hitting the database at once. You won't be doing that.

 

[Idonno]

By Avg home user I"m talking about the fact that its just you.

Yea, no problem I get it, I was just clarifying things.

You use a big SAS array when you have 100+ users all hitting the database at once. You won't be doing that.

Yes, I heard this to but, why. And can that ability translate into anything that could help a single user or a small number of users on a small network of 6 PC's for video editing and just about everything else.

If this were a performance Vs value issue that would make things allot simpler but, it's not, this is strictly a performance issue and any increase or decrease in performance for any one type of similarly priced/specced drive will most likely have allot to do with my purchase decision.

And while I most certainly do appreciate your help, if I knew absolutely nothing about motor vehicles and I needed one for some off-road driving and you said a jeep was better for off-roading than a Honda civic I would certainly want to know why, what makes it so? This is no different!

 

[4745454b]

Because the SAS controllers can handle that many users hitting the drives at once. You mentioned that board had a controller found on their mid range offerings. At that point you start to find cards with lots of onboard memory allowing them to store and execute the many requests that come from 100s of users. As a single user I doubt you will hit the drives hard enough to need the memory found in the controller. (not sure if the controllers on motherboards have the memory. The cards have them for sure.)

I probably won't be able to give you an answer you'd like. Sometimes you just need to trust/believe and take it at that. You can go SAS if you'd like, but I don't believe it will offer you anything you'd need.

 

[Idonno]

Because the SAS controllers can handle that many users hitting the drives at once. You mentioned that board had a controller found on their mid range offerings. At that point you start to find cards with lots of onboard memory allowing them to store and execute the many requests that come from 100s of users. As a single user I doubt you will hit the drives hard enough to need the memory found in the controller. (not sure if the controllers on motherboards have the memory. The cards have them for sure.)

I would imagine that the onboard LSI chipset uses some of the posible 64GB of motherboard ram but, I dont know for sure. Anyway we'll save that question for another day

I probably won't be able to give you an answer you'd like. Sometimes you just need to trust/believe and take it at that. You can go SAS if you'd like, but I don't believe it will offer you anything you'd need.

Well your definitely right about that but, that's OK I don't know everything. I don't expect everyone else to either. Maybe someone else can answer.
As an atheist (actually somewhat agnostic) I'll leave the whole "trust/believe" thing up to the religious people. I often don't completely believe generalized statements without any understanding of the how's and why's behind it. After all it's the how's and why's that give any general statement it's validity. You will also often find that with many generalized statements, once you learn the how's and why's behind it, things might not apply to your precise situation because the "because's" changed everything!LOL

What can I say, I grew up around a bunch of Physicists. Maybe that's how I got this particular type of brain damage. :lol:

Anyway still looking for answers!

 

[Idonno]

Best answer selected by Idonno.

 

[tik4ever]

It sounds like im trying to do the same thing and going between WD re 4 stat vs WD re sas drives both run at 7200 RPM with different controllers just trying to figure out if the satas would be fast enough! I want to run a esxi setup and running a media server that transcodes video on the fly!

the sas drives are $20 more but have 32mb cache vs the sata 64mb cache?

Any advice would be nice!


Thanks!

 

[tik4ever]

I am running this on a dell poweredge 2950 with a perc 6/I sas /sata controller!

 

[Idonno]

It sounds like im trying to do the same thing and going between WD re 4 stat vs WD re sas drives both run at 7200 RPM with different controllers just trying to figure out if the satas would be fast enough! I want to run a esxi setup and running a media server that transcodes video on the fly!

the sas drives are $20 more but have 32mb cache vs the sata 64mb cache?

Any advice would be nice!


Thanks!

I am running this on a dell poweredge 2950 with a perc 6/I sas /sata controller!

Well to completely honest, no one has been able to prove to me one way or another that one is better than the other. Just allot of general statements with nothing to back it up.

As far as your dilemma goes, a 64mb cache is better than a 32mb cache and I know why but, a sas drive is better for a server "because the SAS controllers can handle that many users hitting the drives at once" and I really have know idea why. Other than the SAS controller might have extra memory to help facilitate this.
Although even this doesn't really make allot of sense either, since if a controller that can handle both SAS and SATA, why would any additional memory be allocated to just the SAS drives when certainly both Sata and SAS could benefit.

 

[l00ker]

I have been coming to this site for many years because its always been a trusted source for information and with all the gurus here i cant believe no one has given you a correct response. So take some of the information below into consideration before you choose sata vs. sas

1. sas drive are for enterprise level they are designed for longer time use before a drive will fail.
2. sas is dual ported vs. sata that is single ported. so with a sas drive you will get higher I/O output giving you better performance.
3. sas supports multiple initiators vs sata that has no such capability.
4. sas transfers data in full duplex as vs. sata transfers only at half duplex. so a sas drive each port can read and write at the same time as the sata cannot.
5. sas uses SCSI command set for error reporting and recovery vs. sata that uses the old ATA command set.

i am in agreement if you are a single user on the system then you can save money with a sata setup but for high performance and high i/o i would go for the sas solution.

 

[4745454b]

I can't believe you posted to a 1yr+ old thread that already had a best answer. Next time, just leave it alone.