SCSI RAID-0 ?

[jprebb]

I have been reading the posts on the EIDE RAID-0 vs. SCSI and was wondering, can you put 2 SCSI drives into a RAID-0 configuration? Would this be "overkill"? Thanks for contributing to my enlightenment!

prebb

 

[Guest]

I don't currently use RAID or SCSI, but I assume that they've been using RAID 0 with SCSI drives for a long time. Regardless, here's a link to some RAID info, as pointed out by the KT7 Faq.

<A HREF="http://www.pcguide.com/ref/hdd/perf/raid/index.htm" target="_new">http://www.pcguide.com/ref/hdd/perf/raid/index.htm</A>

Mike

 

[Guest]

Yes, you can use any RAID implementation on SCSI or IDE drives as long as you have the proper RAID card, or use a software RAID. If you want performance, and don't care about redundancy, RAID 0 with SCSI would make sense. If I were spending that kind of money though I'd go for a RAID 5 setup.

 

[Bandit]

The redundancy issue in my opinion is not important for the home user. Think of all the people with 2 hard drives in there system. How many of them actually have a catastrophic hard drive failure? At the very least, you get some warning before things fall to crap. Raid 0 will give an increase in preformance, for the largest bottleneck in your system. You need 2 hard drives for that. Raid 2 gives the preformance and data redundancy, but you need twice the hard drives. With SCSI, I don't think the added cost justifies the minimal security.

The reason this data redundancy thing is talked about so much in all the faqs is because Raid is primairly geard towards companies and institutions that can't afford even the smallest risk of hard drive failure, and who use their drives constantly, under a huge workload, that is more likely to kill the disc over time. For the home user, I would not reccomend the added cost for 4 drives just so if one happens to die all of a sudden, their data is safe. And if you have 2 hard drives, you would be much better served putting them in Raid 0 than Raid 1.

 

[Guest]

I agree with you. If homeuser wanna backup the most important Data, they can either have another Harddisk just for backup (ie. 2 HD on Raid and a Standalone Harddisk) or Removable Storage such as CDR (which is much safer as Lightning and short curcuit can burn the whole Comp but not a Disk that put in the safe . Further Redundancy reduce performance.

 

[Lucol]

RAID 0 is the best performing RAID setup, but also the most unsafe. If 1 drive fails, you lose everything, but like the others said, for a home user that likely doesn't need the system up 24/7, then it's not a big deal. Just make sure to keep copies of your most important information somewhere else. Regardless if it's SCSI or IDE, you'll get a definite performance boost going to RAID 0, than just having seperate drives, and you don't sacrifice any space, as would be the case with any other RAID setup.

 

[Guest]

aaaand SCSI RAID 0 (striped) isn't really going to be that much better (probably none and maybe worse) than an IDE RAID 0 (striped) if you don't use high end SCSI hard drives. So the price truly becomes exponential for a minimal gain in performance. Two good IDE drives in RAID 0 is a quite a bang for the buck compared to what you would have to pay to get better performance from SCSI RAID 0. And if I were spending that kind of money .. I'd go 0+1 . Not many do that though.. just too expensive..

 

[Guest]

One question to ide raid 0: do I need a raid controller (hardware) either onboard or as pci-card, I heard that windows2k supports raid. does that mean it includes a raid software so that i don't need a hardware raid controller?
Thanx

 

[Guest]

No I'm fairly sure you can use IDE in RAID 0 striped or sequential with Win2k Professional. Only Server addition allows fault tolerance for software raid (RAID 1 and RAID 5). And basically the cheap PCI controllers by Promise and Iwill are software RAID really (so in actuality they are just good for giving IDE software RAID capability to Win9x). And both whether with Win2k or these IDE controllers they have high CPU overhead, which is something to consider depending on what you are using it for. Now Promise has a SuperTrak100 for IDE which is hardware IDE RAID. Adaptec makes a hardware IDE RAID card too. But they are both pricey at around 400$. But 250$ for the drives and 400$ for the card are still less than you'll pay for a quality SCSI RAID. So when I say a good IDE RAID that's what I mean.. not a software implementation. But software will work especially with a good processor.. just won't be as good as hardware implementation. Now of course if you do get nice SCSI drives with seek times around 4-5ms and transfer rates around 30-40+ MB/s then yeah it's going to be better than low IO performing IDEs. But you gonna have to PAY for it. And from day to day usage.. it might be hard to justify it, and then yeah as you say, it might be overkill. Depends on your perspective I guess.

 

[Bandit]

You are going to need the Raid controller. In other words, buy a Raid card.

Now, the raid card will be expensive. The ABIT KT7-Raid has an onboard raid controller, giving 2 IDE channels for an ATA100 Raid controller, and then has 2 more standars IDE controllers, for a total of 8 devices. It's an awesome board, and it only runs about 200 bucks canadian. It you are running an Athlon/Duron processor, it is a great buy if you want to impliment IDE Raid. Personally, I am just waiting to get the funds for a couple of decent ATA100 7400 RPM drives to put in Raid 0.

 

[Grizely1]

As posted before, RAID 0 with SCSI is existent but it doesn't gain very much performance, and none at all if you're not using high end drives. And high end SCSI drives, <i>especially</i> two of them, is big $$. Just for fun let's go down the list:

Seagate Cheetah 15k 18.3GB (Fastest drive you can get) - goes for about $430, which is doubled so <b>$860</b> for hard drives
and for the controller, I think I saw a SCSI RAID controller for 300 or 400 dollars....

 

[Guest]

The Abit is just another example of software raid with high cpu overhead. It works I guess. I just don't think it's as good as having the IO work done by the card.

 

[Guest]

yeah I took a look .. saw a AAA-131 adaptec used for 285$. Two cheetahs would stretch that 80MB/s though. There was a new 2100s offered by PCNation for around 370$ (good luck with them..I'd be scared to get that since they are the only mail-order company offering it for that price.. most are over $400).

 

[Guest]

Î got confused. You mentioned promise's raid controller twice. Is the fast track100 a good solution or will eat up the processor. I'm using my Pc not for gaming but photoshop and 3CAD, etc. so I'm opening constantly big files from the harddrive which really seems to be the bottleneck. (besides the missing duoprocessing capability of AMDs)
So Fast track 100 and 2 IBM Deskstar will be a performance boost, compared to only one drive.
Did you read Tom's article about building a raid card from the normal ata adapter (ATA100 card only 40$US)
http://www5.tomshardware.com/storage/00q1/000329/index.html

 

[Guest]

ok first.. I mentioned the promise Fastrak 100 and the Promise "SUPERTrak 100". They are different.. in price and performance. The latter is a hardware implimentation of IDE RAID.. and will do a little better with just a 2 drive striped RAID 0 compared to the Fasttrak depending on what you are doing and your CPU. (it's only 2 drives so there is less IO overhead for the cpu to handle, but there will still be more than if you use a hardware controller). I still think in your case working with CAD files you'd see better performance from a hardware implimentation especially with only one cpu. (Adaptec offers one too that I like.. you won't max out the 66MB/s bandwidth with only two drives).

If you don't want to invest in the hardware rig, I would only suggest using the Fasttrak if you are using Win9x. Are you? Otherwise just use Win2k or NT's software implimentation for RAID. And yeah a striped RAID 0 of anykind will probably increase performance for large CAD files.

As for Tom's review, that was for a Fasttrak 66 not a 100. The operation for converting a 100 is different and takes a little more soldering and patience.. and maybe some luck. You don't really need the 100 with only 2 drives..so the 66 easier to do..it's even cheaper.. it does what you want for Win9x so use it.

 

[Guest]

thanx so much for your help! what do you think about onboard raid like Abus KT7-Raid or others? they will probably do the job!?

 

[Bandit]

I have personally not used the raid support of the KT7-Raid, but from everything i have read from those who have, the CPU overhead is quite acceptable.

Do you really WANT to upgrade your motherboard? If you plan on doing that, then you can kill two birds with one stone. But if you are happy with your current setup, and simply want Raid support, you would probably be better served getting a promise card.

 

[Guest]

yes.. I too seriously doubt that the Abit onboard is any better than the peripheral controllers... so unless you are looking to change boards.. I'd leave that one alone.