SATA Versus SCSI

[owensdj]

Any thoughts on whether Serial ATA can take some of the SCSI market share in the low to middle range of servers? I believe I read where SATA includes Tagged Command Queuing, which eliminates one of the biggest advantages SCSI has over Parallel ATA.

 

[woolmilk]

SATA is the replacement for IDE / ATA drives. Main feature is the ease of installation with thin cables, single connection and the elemination of this annoying master slave concept. From what I read and hear it wont add any performance advantages at least in the first generation (cause the drives are mainly the same) but it offers some additional headroom for the future.

It will replace IDE in a few years and maybe some of the SCSI market will jump on SATA (If all you need is cheap storage with features like hot pluging).
But as long as all highly reliable and fast drives are SCSI, it will not replace it. So this is mainly in the hands of drive manufactors and I m looking forward to see some improvements to the drives itself.

 

[ElFenix]

scsi also includes a lot of data verification that sata doesn't, afaik.

 

[RSMemphis]

Why go SATA when you can go FC (fiber channel)

FC has a higher throughput, most SCSI HDs are already released as FC versions.

Edit: A lot of people see Firewire as a sort of serial SCSI, but I think it's really FC that is the equivalent.

 

[ElFenix]

scsi is serial... isn't it?

 

[stevewm]

Originally posted by: ElFenix
scsi also includes a lot of data verification that sata doesn't, afaik.

Actually thats one of SATA's new features. It does full error checking and correction on both the commands and the data itself.

Obviously thats a very simplified explanation. If you want to read more detail on SATA's ECC (error checking and correction) download this: http://www.serialata.org/collateral/zipdownloads/SerialATA10Gold.zip

Its a zipped PDF file, open it and goto page 269.

 

[woolmilk]

No, SCSI is a parallel bus with, uh, >32 wires.
A serial bus has only a few cables. Its simply that technology has advanced and its now easier to integrate a high speed interface with a single pin than synchronizing lots of data cables. You could plug up to 32 devices on one SCSI cable. Im sure they are developing SATA cards that support 16 or more drives but then you will need 16 cables, thus reducing the advances of small cables a bit. But with drives reaching capacities of more then 300GB I m sure you dont need that many drives.

FC is a nice peace of hardware, but will be left for big servers and costs tons of money.

 

[Goosemaster]

Originally posted by: RSMemphis
Why go SATA when you can go FC (fiber channel)

FC has a higher throughput, most SCSI HDs are already released as FC versions.

Edit: A lot of people see Firewire as a sort of serial SCSI, but I think it's really FC that is the equivalent.

Have you realized how much FiberChannel COSTS? Generally out of EVERYBODY's league.

Anywyas, Fiber Channel is basically for mad server setups and long distance connections...such as iscsi etc.

 

[tcrosson]

I remember reading in an article somewhere that Serial SCSI is in the works. However, it said we're looking at up to 2 years before anything becomes reality.

 

[SUOrangeman]

Serial Attached SCSI

-SUO

 

[Goosemaster]

Originally posted by: tcrosson
I remember reading in an article somewhere that Serial SCSI is in the works. However, it said we're looking at up to 2 years before anything becomes reality.

iSCSI is Sooooo much cooler...



Uses SCSI over an IP so it can literally be anywhere....



Scsi in the shower
Scsi next to my flowers
Scsi in the yard
Sci ain't no piece of lard
Scsi is now tame
Scsi poem, you are so lame


<---big fan