Western Digital WD Caviar Blacks Raid Problem

[captainkall]

Hello guys Kall Here,


Long time reader first time Poster, So Here is the situation I am building a new computer, I hit a snag that everyone is too scared to try I understand and respect that this may sound crazy but I Have my heart set on the Western Digital Caviar Blacks, namely Model number WD1002FAEX1 now here is were I Have Problem I have my heart set on 4 of these guys in a RAID.

Cool you gurus now think "Those in RAID 0 is fast, but no still... It will be no match for my 4 disk SSD RAID 0." But wait... I want RAID 5. You now think "THIS IS MADNESS!!!(to which I add "This is Sparta. but that is hardly the point.") HAVE YOU NOT READ THE DATA SHEET IT SAYS RAID 0 AND RAID 1 ARE YOU MAD?!?" But I have and I am wondering is there ANYONE who Has tried this before and Failed. No one seems to talk about it directly and everyone seem to scared to try, In spite of the fact its possible the advise maybe for the main reason of a Up Sell to the RE, This is a home gaming computer not a 24 7 server. call me a sceptic if you must but it May help many to know.

THE question remains this:
Can Western Digital Caviar Blacks be used in raid 5 at home?

So has anyone Tried of am I off on a pioneers journey?

I need answers Please help me.

Oh yeah I forgot I am running a 2 disc SSD raid 0(2x OCZ Agilty 3 60GP) now for my os, I wanted 3 long story... low stock in the most Isolated city on earth (well maybe the second most depends who you ask).

 

[sminlal]

Sure, they can be used. The big problem with RAID-5 is that performance is very bad for writing. They also work better with a dedicated RAID controller card that performs background integrity checking because RAID-5 is susceptible to data loss due to single-bit errors when you start getting into the larger volume sizes.

 

[captainkall]

So when doing big writes it may Loss data causing a error... hmmm then whats all this talk about TLER?

And what sort of decress in write speeds are we talking about? 50% 10% 90%? cause if its a matter of say 10-30% under raid 0... Come on.

 

[sminlal]

The issue with writes is performance, which is typically something on the order of half as fast as an ordinary, non RAID drive.

The issue with reliability is that if you have a drive that fails and if you have a large enough RAID volume, there's a chance that you'll encounter an error while trying to rebuild the RAID set onto the replaced drive. A hardware RAID controller that constantly scans for errors in the background goes a long way toward eliminating that as a source of concern.

TLER is recommended so that the RAID controller won't declare a drive dead if it happens to be taking a long time to try to read and re-read marginal data from a sector. In a TLER-enabled drive the drive will report an error within a limited time, and that lets the RAID controller recover from the error rather than giving up on the drive.

 

[ahthurungnone]

I just installed 3 Caviar Black drives in RAID 5 and I don't notice any write issues. RAID 5 is mainly used for servers for "read" applications like movies etc. The write times do decrease, but normally I am not saving information as much as I am simply reading info.

The only issue I have discovered is when I install programs on the RAID5 (rather than my boot drive) which causes issues. Perhaps this is due to RAID5 losing write data but I have no idea.

 

[sminlal]

The only issue I have discovered is when I install programs on the RAID5 (rather than my boot drive) which causes issues. Perhaps this is due to RAID5 losing write data but I have no idea.

When you say it "causes issues", what specifically is the problem? If it's just slow install times, that's normal for RAID-5 because of its poorer write performance. But RAID-5 shouldn't loose any data.

 

[JordoR]

In the past I have used 6 x 1TB WD Black Drives in RAID 5. I never had a single problem and in fact, running these for 3 years I luckily didn't have a single drive failure.

I would not call you a pioneer of this it's been done many times before.

 

[ahthurungnone]

The install fails or the program doesn't run correctly stating it cannot find files. That's what I mean.

FYI: I am the Pioneer of Stupidity!

 

[sminlal]

RAID-5 won't be the cause of those kinds of problems. My guess is that the programs you're trying to install to the non-OS drive aren't flexible enough to be installed there. Some (poorly-written) programs assume that all of their files are going to be on the OS drive and they don't work properly if they're not. That's a programming issue that has nothing to do with RAID.

 

[captainkall]

Sounds good I thought it would work. Thanks Guys Glad to get it out there. I will try it and report back that way we will have 3 points of view saying how it works. it will be good for those of us how are building a PC.

 

[captainkall]

Best answer selected by CaptainKall.

 

[captainkall]

The Rig is Stable but now. Bulldozer disapointed... but if the price comes down from AUD $315 I will get a 8150 or a 8170 next year. Maybe the next AM3+ set will be okay... not likely but we can hope.

 

[tomatthe]

I ran 3 of these in Raid 5 a few years ago, and all worked well until one died and I ended up with one of the newer models. The drive that I got as a replacement would drop out of the array every few days, and continued to do this after having that drive replaced as well. If you read WD's info it definitely says they only support these drives in Raid 0/1 which you can take as them trying to get more money for the RE series or that they actually will not work properly which was my experience.

I would never try to use this line of drives in a Raid 5 again.

Some of them you can enable tler, but some of them you can not. I was not able to with the replacement I got, and it simply would not work in a Raid 5 set at that point.