Lets face it: Desktop RAID 5 is BS

[Ratman6161]

In the Anndandtech article AMD's SB750: Enabling Higher Phenom Overclocks? they say: "SB600 and also addresses one feature flaw in the SB700. That feature flaw is RAID 5"

Now lets get real. Who really uses RAID 5 on a desktop system. Yes, I know there are some who do. but if you are in that category, you are probably more than willing to go out and buy a real RAID card rather than rely on some jacked up crap built into a desktop chipset.

Why do I get upset about this? Because the effort that went into that functionality that very few will ever use could have gone into something that would have benefited users at large. The ultra high end crowd addressed by the RAID 5 functionality will just have to to buy a card.

So why is this a "flaw". Who really cares?

 

[taltamir]

true, its more of a marketing thing... "our mobo isn't inferior, it ALSO supports raid5"... ofcourse you should never, EVER use it...
upgraded the bios? oops, the array is gone! (although potentially recoverable, but risky)
reset the cmos? oops, the array is gone! (again, potentially recoverable, but risky)

Not to mention the most atrocious performance ever (10 mb/s write performance, 30-40mb/s read). compatibility issues, and so on.

But the review did note that it was a feature to check off of the list. It is pure marketing bs.

 

[Pantlegz]

It's been a while since I've messed with RAID, but isn't RAID 5 the same as RAID 0+1? If so, wouldn't you gain the performance of RAID 0 and have the security of RAID 1..or is it the other way around? Either way I agree it's something that isn't used often, if at all. I guess SATA (on the same controller) RAID 0 (or 5) would be worthless as only 1 HDD reads/writes data at a time. SCSI RAID ftw I guess...

 

[Ticky]

I use RAID5.... though I bought a card. It's good when your sloppy about backups. 'Course, remember kids, "Raid is not a backup".

 

[Fullmetal Chocobo]

I use RAID 5, although I would never do it off of the motherboard.

 

[Keitero]

Originally posted by: Pantlegz1
It's been a while since I've messed with RAID, but isn't RAID 5 the same as RAID 0+1? If so, wouldn't you gain the performance of RAID 0 and have the security of RAID 1..or is it the other way around? Either way I agree it's something that isn't used often, if at all. I guess SATA (on the same controller) RAID 0 (or 5) would be worthless as only 1 HDD reads/writes data at a time. SCSI RAID ftw I guess...

RAID 5 is NOT the same as RAID 0+1. RAID 5 is striping with distributed parity and requires 3 drives or more. RAID 0+1 is striping with mirroring and requires 4 or more drives.

I do agree that if people do any other RAID types other than RAID 0 or 1 that they use a RAID card to do so.

 

[Christobevii3]

Raid 5 works fine for extra storage. On my old 570sli i had raid 1 for the boot drives and 4 400's in raid 5 for 1.2TB. I now have a hardware controller with 4 1TB that i'll expand out to 8. I like the ability of having the single parity drive so that i can lose one drive and not lose my stuff. Also, the fast reads are nice.

So I run raid 0+1 with the 400's now and raid 5 with the 1TB's.

 

[Yellowbeard]

I built a NAS server using a P5K Deluxe, 5 x 500gb drives in RAID-5, with the OS (Freenas) on a 1gb flash drive. I chose this MOBO as it has 6 SATA headers which leaves 1 for the optical drive. It works flawlessly. It was an inexpensive way to build a NAS server and not have to buy a RAID card.

 

[RebateMonger]

Here's a detailed comparison of RAID 5 and RAID 1+0.
(This link is part of a larger site, BAARF.COM )

It's also the reason that I don't use RAID 5 anymore unless I have absolutely no other choice.

 

[solog]

What do add-in Raid 5 cards start at (price)? Can you add drives later on easily?

 

[taltamir]

i dont see a reason to EVER use raid5... if you are storing unimportant data... no raid at all or raid0 if it needs to be fast.
If you are storing small amounts of important data, raid1, speed and important? raid10 or 01.
Low budget or massive amounts of data? raid6.

Any situation that would force you to get raid5 over the better raids, you are better off getting raid6 instead.
And it should be OS based (disable raid in the card, use raid in the OS) or fully accelerated Controller card based (300$+ cards), not CPU based controller card / southbridge.

 

[RebateMonger]

Originally posted by: taltamir
i dont see a reason to EVER use raid5... if you are storing unimportant data... no raid at all or raid0 if it needs to be fast.
If you are storing small amounts of important data, raid1, speed and important? raid10 or 01.
Low budget or massive amounts of data? raid6.

My thoughts, exactly. I've seen WAY too much lost and corrupted data on both hardware-based and software-based RAID 5 arrays. Well, I guess I SORTA' like RAID 5, because it makes me lots of money when they fail..... , but I won't recommend RAID 5 to a client anymore.

 

[Ratman6161]

Originally posted by: Yellowbeard
I built a NAS server using a P5K Deluxe, 5 x 500gb drives in RAID-5, with the OS (Freenas) on a 1gb flash drive. I chose this MOBO as it has 6 SATA headers which leaves 1 for the optical drive. It works flawlessly. It was an inexpensive way to build a NAS server and not have to buy a RAID card.

Ok, I can see that. But I did say it seemed pretty useless on a "desktop system". You are using a motherboard that was intended for the desktop - but you are using it as a server, not a desktop. And, for this purpose, wouldn't it really perform better and be more reliable etc with an add in hardware raid card?

 

[taltamir]

no, it will be less reliable... a hardware raid card creates a single point of failure, and when it fails you have to track down an identical card and find out how to restore the array on it.
With a OS based raid it means that the drives appear as seperate drives on the mobo, the mobo has raid disabled. The operating system manages the data between them in a raid fashion. The drives are unreadable in an OS that does not support that implementation, but if it is then they are easily transferable. I transfered ZFS arrays as a test between solaris, nexenta, and freebsd. in every OS it was as simple as typing "zpool import -f tank" (-f to force import, since it says that the drives are in use by another operating system)

 

[beef5stew]

:shocked:

I just built a RAID 5 desktop machine on a Gigabyte GA-x48-DS6 motherboard. I'm using 4 of the WD SE16 640GB hard drives. I have to admit, I built it because my last machine just died due to a HD failure. I've seen a marked improvement on Read/write times since I went to RAID 5. I'm averaging about 132M/sec. With burst speeds getting close to 200. Vista boots in 8 seconds flat.

I have an external USB drive that I use to back-up my important files (pics, home video, etc) but the rest of this space is used mostly for music, and Home Media. I did do one test and pulled out a hard drive, reformatted it and plugged it back in. Took the machine about 14 hours to re-build the array, but I was back in business.

If you expect to blow up your system regularly, I would say, this is not for you, but I have a "play" system that I blow up...this one is only for production.

Beef5stew

 

[taltamir]

beef stew... try two RAID1 arrays, or a RAID1+0 array for even better speed and reliability.

 

[Madwand1]

Originally posted by: Ratman6161
In the Anndandtech article AMD's SB750: Enabling Higher Phenom Overclocks? they say: "SB600 and also addresses one feature flaw in the SB700. That feature flaw is RAID 5"

Thanks for the note about its availability in some AMD chipsets now. I'd missed that. In time I might try it.

I've been running an nVIDIA RAID 5 and an Intel RAID 5 system for a while now, in addition to a couple of add-in controllers and test systems with Linux-based RAID. Each have their strengths and weaknesses, and place. I'd be interested in checking out AMD's. It's good to have many choices and competition; to not be forced into Intel for example when you want this feature relatively inexpensively in a Windows-based system.

This thread had some nVIDIA and Intel RAID 5 benchmarks and discussion:

http://episteme.arstechnica.co...009426831#123009426831