SATA II vs SAS
SATA II 7.2K RPM vs. SAS 10K RPM
I know that SAS is probably faster but how much faster is it than SATA II ?
I know that SAS is probably faster but how much faster is it than SATA II ?
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So the 3Gb/s is the interface speed? This number seems meaningless. Why don't they give us the sustained transfer rate then? The only specs they seem to give are 3Gb/s and RPM. Thanks for the info.
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I am planning to use Raid 1
"... So the 3Gb/s is the interface speed? This number seems meaningless " ==> Yes, it's the interface speed; and although it's not completely "meaningless", I agree it's deceptive. A lot of people think that means it's a much faster drive ... but in practice there's virtually NO difference in performance between the same drive with an ATA100 interface and a SATA-II interface (the difference is measurable; but almost certainly not noticeable).
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I noted this idea above, but it's nicely stated in the article mcp_jon referenced: "... It's important to emphasize that SAS is an "interface" -- the circuitry and interconnection used to move data to or from the drive. SAS has virtually no impact on the mechanical design or operation of the drive itself (e.g., the platters, heads or other drive components)."
... in other words, it's the 10,000rpm DRIVE that's faster --> NOT the fact that it's SAS. You can get equivalent performance with a nice 10,000rpm SATA drive => a WD Raptor 150GB comes to mind (it's "only" SATA-150, but will outperform virtually any SATA-II drive).
... in other words, it's the 10,000rpm DRIVE that's faster --> NOT the fact that it's SAS. You can get equivalent performance with a nice 10,000rpm SATA drive => a WD Raptor 150GB comes to mind (it's "only" SATA-150, but will outperform virtually any SATA-II drive).
The major difference is that SCSI is attached to the same channel, and Data must run in the same channel. SAS is like a Backplane where every disk interconnect and eliminates cabling between disks, SERVER Speaking :). In Workstations it works just like Sata, where every disk goes to a Physical Port on a Controller, wether it's Onboard or on a PCI card .
Hope this lightens up your mind !
Best Regards !
Hope this lightens up your mind !
Best Regards !
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Thanks for the help. I think I will go with Raid 1, 300GB, 10KRPM, SAS drives. I want this server to be fast and reliable.
Good choice ... it will indeed be both fast and reliable :-)
You bet it will !
Best Regards !
Best Regards !
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