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Cman
08-09-2005, 12:35 AM
Which would you use when?
For media?
For programs?
For OS?

Any thoughts and suggestions?

I wish I could have both at the same time! A perfect backup of everything, while also having speed increase for media with multiple HDD.
Is there a way?
If so, how?

T.I.A.

TopherMartini
08-09-2005, 01:07 AM
Here's a link with some useful info on RAID types (http://www.bytepile.com/raid_class.php).

RAID 0 (Striping) and RAID 1 (Mirroring) define two ends of a spectrum. With Striping you gain maximum performance benefit by striping data across all RAID set members, but what you gain in performance you lose in recovery capability. RAID 0 has no parity data, so in the event of RAID set member loss (one of your drives going bad) the entire array goes with it.

Mirroring is the opposite of Striping, all data is distributed evenly across all RAID set members. If one drive goes down you have all the remaining drives to sustain the array's integrity.

Striping is used in situations where performance is paramount and the data is backed up elsewhere. Sometimes RAID 0 is used for video ingest since the video is always back on tape... so you can always recapture the source.

Mirroring is used in situations where array reliability can never be degraded, most commonly web sites or high-volume file servers.

Most applications of RAID storage need somewhere between RAID 0 & 1, because they want performance of multiple disks but need some sort of array recovery in the event a RAID set member goes bad.

RAID 3 (Striping with Dedicated Parity) and RAID 5 (Striping with Distributed Parity) are commonly used here. With both of the RAID types you gain the performance benefit of striping across multiple drives, yet you gain the ability to fail a drive and successfully rebuild it from the parity data on the remaining drives.

Most RAID arrays are used for media storage to gain performance and reliability that you cannot get off a single drive. It's important to remember that RAID DOES NOT REPLACE BACKING UP! File system corruption can occur regardless of the RAID type you use...

The best advice anyone can give you is to check out a friend's setup that uses RAID for storage. You can talk about RAID configurations forever, but it's all about finding which combination works best for your needs :thumbsup:

OC-NightHawk
08-09-2005, 01:09 AM
I personally use raid 0 for my system drive. All my important data like my work is on a bulk storage drive and archived onto dvd. If you want both then I suggest you look into Raid 5.

TopherMartini
08-09-2005, 01:15 AM
I personally use raid 0 for my system drive.

It'd be interesting to see the performance improvement you get working off a 2-drive RAID 0 vs. a single drive.

Some of the performance you gain from a RAID 0 can be lost due to VM paging. The more applications you have open at once the more of an issue VM paging can become.

enygma
08-09-2005, 02:32 AM
I had run a system on RAID 0 before. There were 2 drives in the whole system so I was forced to put the OS and software on the RAID 0 array.

You won't notice much of a speed up in OS boot up speeds, but application installations from hard drive were noticeably faster. I also noticed some pretty nice speed improvements in loading up Battlefield Vietnam as well. We had 3 systems loading it simultaneously. The system on the RAID 0 loaded the map almost 2 times faster than the next fastest non-raid system.

Keep in mind though, you sacrifice data security in favor of performance in RAID 0. No redundancy = screwed data, even if 1 drive goes on ya.

OC-NightHawk
08-09-2005, 02:57 AM
It'd be interesting to see the performance improvement you get working off a 2-drive RAID 0 vs. a single drive.

Some of the performance you gain from a RAID 0 can be lost due to VM paging. The more applications you have open at once the more of an issue VM paging can become.

I'd say it's a lot considering the two drives are Seagate 15000RPM SCSI drives running on a PCI-X 133MHz slot all by themselves. :buttrock:The real deciding factor for the cpu hit is how good the card is. I'm using a Adaptec 39320A-R (2060900eu) SCSI Controller It doesn't tax my dual Xeon that bad imo.

It screams but the array size is a bit small for my taste ~60GB formatted total between the two. But thats what two 200GB IDE drives are there to make up for. :D It has a great side effect on games where load time is non existant. For me the bottle neck of a 7200RPM drive is worse then a very small performance hit.

It's worth every penny. If you can get a pair of 10000 RPM drives they'll serve you well as well too if you can't aford the faster 15000 drives.

"Keep in mind though, you sacrifice data security in favor of performance in RAID 0. No redundancy = screwed data, even if 1 drive goes on ya."
Very true, but thats what bulk storage and optical media are for. :)

enygma
08-09-2005, 03:02 AM
Very true, but thats what bulk storage and optical media are for
Or if you have the extra cash and room on the controller, RAID 0+1... :D

OC-NightHawk
08-09-2005, 03:09 AM
Or if you have the extra cash and room on the controller, RAID 0+1... :D
True but scsi drives are kind of pricy per GB. :)

Cman
08-09-2005, 03:20 AM
Thanks for all the replies.

Looks like my best bet is RAID 0 with a serious daily backup policy.

Hmmm. So troublesome.

OC-NightHawk
08-09-2005, 03:29 AM
Thanks for all the replies.

Looks like my best bet is RAID 0 with a serious daily backup policy.

Hmmm. So troublesome.

Don't worry about backing up the install itself, just your work. You should be backing your work up any ways. I would make a image of the system drive though for quick reinstalls when the system needs it.

Cman
08-09-2005, 03:33 AM
Don't worry about backing up the install itself, just your work. You should be backing your work up any ways. I would make a image of the system drive though for quick reinstalls when the system needs it.

yeah I know.
I have recently had a few HDD crashes that happened in "lucky" timing - but it's got me spooked as I don't backup on a regular basis.

That is now going to change.

Originally I thought to use an array as backup and speedier read times of video and frame sequences - but I'll just get a beefy external drive for backup.

rebo
08-09-2005, 05:46 AM
Im looking to run two 74GB WD Raptor 10,000 SATA drives in raid 0 configuration. It will be for my system drive only. Theory being if a drive goes I can reinstall my software.

Can you partition raid 0 drives sets just like you can partition an ordinary HDD?

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