SAS vs SATA real-world!

I understand all of the differences of SAS and SATA interfaces and drives... but an looking for some real world advice...

In a 3-drive RAID 0 set-up, would there be an appreciable difference between 15k rpm SAS drives and 10k rpm SATA drives?  Or would the interface become the limiting factor since the RAID 0 set-up is effectively increasing the overall read-write performance by writing 1/3 of the data to each drive?

I know in a single drive to single drive comparison that the SAS 15k would probably show better read-write times... but in the RAID 0 3-drive set-up described above, would there still be a difference?  And if so, would it be noticable and worth the higher price?

Any links to real world comparisons of SAS/SATA in RAID 0 set-ups would be greatly appreciated.

Jeff
jeffs1Asked:
Who is Participating?

[Webinar] Streamline your web hosting managementRegister Today

x
 
kode99Connect With a Mentor Commented:
If you have seen this article at Tom's you may want to check it out.

http://www.tomshardware.com/2006/04/07/going_the_sas_storage_way/index.html

It includes some benchmarking that you may find useful.

0
 
pgm554Connect With a Mentor Commented:
Depending upon the buss slot there will be real world differences(64 bit 66 mhz vs 32 bit 33 mhz) in the amount of data pumped through.
Bigger pipe,more data.

Controller type SCSI RAID generally has an onboard processor (i960) and has caching capabilities and will give you overall better throughput and performance.

What are you trying to do?File server.video?

And just a reminder,RAID 0 has NO redundency.
If you loose just ONE drive,kiss you data goodbye.
It ain't coming back.


0
 
Duncan MeyersConnect With a Mentor Commented:
>In a 3-drive RAID 0 set-up, would there be an appreciable difference between 15k rpm SAS drives and 10k rpm SATA drives?  Or would the interface become the limiting factor since the RAID 0 set-up is effectively increasing the overall read-write performance by writing 1/3 of the data to each drive?

Yes, purely because of the spin speed. An addaitional performace edge that SAS has is that it implements the the full SCSI command set and technologies such as native command queueing - which is only supported in SATA II drives *if* you have a controller that supports it. I'd expect the SAS drives to be 33% faster in most instances. The point is, however, that you'll really only see a performance difference when the system is under stress - that is write cache on your RAID controller is full and the controller OS/controller is queueing writes. In this scenario, there will be an appreciable and substantial performance difference with the SAS drives.

The other important factor to note is duty cycle. SAS drives are made to run 24 hours a day, seven days a week. SATA drives are not. If you'll be using these drives in a departmental server or a box that is going to get hammered then your choice should be SAS - no question.

Finally, as I'm sure you're aware, RAID 0 is not RAID! It has zero, zip, nada, none, no redundancy - if you lose one disc, you lose all your data.

 
0
 
Duncan MeyersCommented:
OK by me...
0
All Courses

From novice to tech pro — start learning today.