SCSI vs IDE RAID

[Marine]

I know a lot of articles lately have advocated the point that SCSI has been overtaken by fast IDE and SATA solutions. So, on my antiquated machine with both protocols, I ran the Quick Bench test separately on the two RAID storage profiles I have in this machine.

The first is two IBM DeskStar 36MB SCSI disks in RAID 0
The second is two Western Digital 120MB 8 MB cache disks in Raid 0

I have the operating system (WinXP Pro) on which I ran this test installed on the IBM SCSI array.

The results follow:

SCSI Array:
2.0 kb = 310 kb/s
256 kbs = 24.24 kb/s
4 MB = 75.07 mb/s

IDE Promise Array:
2.0 kb=186.5 kb/s
256 kb=11.85 kb/s
4 MB= 51.49 mb/s

These tests were run on freshly defragmented drives using Executive Software Diskeeper v 8.0

So... it appears that magazine articles lately notwithstanding -- the SCSI solution still has some advantages, and I should add that my 3920 Adaptec SCSI adapter isn't really "cutting edge", being some two years old. The on-board IDE RAID Promise chip on my ASUS baseboard, however, is cutting edge, so the conclusion that I draw from this little test is that SCSI still has utility for fast systems. I put my OS(s) on my SCSI RAID and my programs on my slower ATA RAID array.

My only point in posting is that SCSI has been so dissed lately in favor of the fast IDE/SATA solutions that I thought I'd post some real-world numbers.

Best to all, Semper fidelis!

 

[Peter]

It would be even faster if you weren't using ooooold SCSI drives, and if you weren't crippling the dual U320 SCSI (640 MB/s bandwidth requirement) on a 133 MB/s PCI bus.

 

[Carbonadium4]

Ill go try this later.. i just converted from 1 boot + mirror raid to a raid 5 w/4 drive. Quantum 10K 8mb cache..

On my single scsi 10k boot, sandra said all my stuff was way under a 7200 ide.. so i wanna see what I get here..

 

[Zepper]

I like SCSI too (have 4 little scuzzers in my box), but this thread is OT. Belongs in Peripherals.
.bh.

:moon:

 

[prometheusxls]

The discussion of RAID that I ahve seen letely on many hardware sites is way too simplified to offer any real insights into the true value of raid. The #1 goal of raid is data redundancy, #2 goal is performance. RAID-5 is for server environemnts where DATA integrity iand volume access speed are both important to keep things up and running. RAID-0 Striping is also used in some limited workstation setups and other specialty systems where data access speed is key for certain processign neesd like video encoding. There are a ton of different raid options. In general you are best off with a single drive than a RAID.

 

[gnumantsc]

But is that really justifying the added cost per se if you were running a server? Yes the harddrive is still the slowest thing in a computer (if you exclude cd\dvd\floppy drives)

But if I had the choice on a machine I'd rather spend the money on a CPU and more memory than "throwing" it on a SCSI design with much smaller HDs

 

[prometheusxls]

The only thing that justifies the servers cost is the duty that the server will be performing and how well it either meets or doesn't meet those needs.

I suppose my rebuttal is that it seems that the cost of enterprise level raid is such that the cost to performance ratio scales fairly well between SATA and SCSI, If you need higer performance then you obviously need scsi. For an enterprise level file server, I would suppose that the SCSI setup would be prefered. Granted you do get more physical space with SATA, but that isn't always the determining factor, or necessarily even a relevant factor. I mean not every server needs terabytes of storeage. It depends on the needs of the organization. Granted for workstation level SCSI implementations I deffinately see SATA raid as an alternative to SCSI. For more modest "Budget" servers you will probably be seeing implementations as well...