4TB Raid 1 to Raid 5

[davidst95]

Hi, I currently use a SSD for my OS and applications.   I have two WD Black 4tb in a RAID 1 configuration that I use to store backup images and other miscellaneous.   My friend will sold me his 4TB (same model as mine) for $150.   Would it be a good idea to set up a RAID 5 configuration?   I read it slows down write speeds but not sure if it's significant.  I ran CrystalDiscInfo on his drive and didn't really find any issues.   Thanks.

 

David

[Mighty_Miro_WD]

Hi there @davidst95!

 

You can setup RAID 5 with 3 Blacks if you already have the drives, but I wouldn't suggest you to do so.

 

WD Black is designed as a stand-alone HDD and doesn't have the necessary build-in features for non-consumer RAID setups (RAID 0 and RAID 1). For example such features are low operating temperature and TLER, which helps the drive recover faster in case of read/write error and the drive doesn’t drop off the RAID. You can read more in this KB article:

 

http://wdc.custhelp.com/app/answers/detail/a_id/1397/session/L2F2LzEvdGltZS8xNDE1MTczODg5L3NpZC9aSGgxb0U2bQ%3D%3D

 

Hope this helps.

 

Cheers!

[ChineseChef]

Converting from raid 1 to raid 5 can be done by more top end cards, but really, it would likely be faster and safer to just move all the data off array, rebuild the new array, then move the data back on.  Naturally, this means you have to have enough space to hold everything you have while the drives are being reconfigured.

[davidst95]

Thanks for the reply.   Would a RAID 5 increase sequential read speed.   I also have a SSD drive.   If I use a portion of the SSD drive as a chache, will it help with the slower write speed of a RAID 5 configuration?

 

David

[ChineseChef]

Are you using this as a working storage area?  Or just as data storage? 

 

If you are just using it as storage, you likely won't notice much difference.  If you are actually running programs off these disks, then the SSD cache would likely help, but this requires that your RAID software/hardware supports all that.

[davidst95]

Thanks for the reply.   I use my SSDs for my OS and Applications.    I been using my convental hard drives in RAID 1 for storage and backup of my SSD drives.    The reason why I ask about sequential speed is part of my job is test out new OSs on VMWare.    I was thinking that I can create a VM faster if I had quicker sequential speed on the HHDs.  

 

Also, I have software that allows me to use caching in the RAM and on the SSD.   I think Intel has software that sort of does the same thing.   Thanks.

 

David

[ChineseChef]

I use VMware a lot, and unless you have good raid card, that can use ssd caching correctly, or you let vsphere handling the caching, you won't notice an improvement.  Likely the opposite. 

 

In general, RAID 5 and 6, are for size.  They are pretty much always worse on speed.  Since you get huge write and general access penalties.

 

If you were to get a fourth drive, and run raid 10, then you would notice some good speed increases.  But don't ever plan on raid 5/6 being a speed increase.

[davidst95]

Thanks for the response.   I have a Gigabyte Gamin GT Z97.   I has an Intel RAID that supports 0/1/5/10.   Is the performance of RAID 10 on the built in Intel controller acceptable?  

 

David

[ChineseChef]

Thanks for the response.   I have a Gigabyte Gamin GT Z97.   I has an Intel RAID that supports 0/1/5/10.   Is the performance of RAID 10 on the built in Intel controller acceptable?  

 

David

 

For raid 1/0/10, onboard/built-in raid controllers work just fine, with the only limitation being the number of ports you have.  Should be plenty fast and reliable from a controller standpoint.

 

RAID 5 will work with onboard, and will function just fine, but won't be super great.  This is usually fine for regular home uses though, as home users aren't usually pushing the limits of what they want the hardware to do without understanding their needs.