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How software RAID-1 works and how to configure? RRS feed

  • Question

  • I'm going to make software RAID-1 of disk C: and partition D: (same sized) of another disk.

    1. How RAID-1 reads and writes in W8.1 – will it read/write as slow as double speed of slowest disk? I think writing commands for slowest disk should be queued to let faster disk work fast.
    2. If software RAID-1 supposed to sumarize reading speeds of disks – how to disable reading from slowest disk? (if fastest more than 2 times faster)

    I think that this raid-1 configuration is a future favorite of all usual users because in case when any disk fails it lets (lossless) to continue using OS.
    The rest of 2nd bigger disk (which 
    may be raid-0) in my view should only host files of torrents and exclusive or personal files/libraries mirrored to cloud storage(s). If 2nd disk is SSD – it's usually faster (multichannel) so (in this cases) the partition of it is better to be sys. and 1st disk can be raid-0 (hardware).


    • Edited by rromm Thursday, July 17, 2014 11:47 AM
    Thursday, July 17, 2014 11:39 AM

Answers

  • Hi,

    In Windows 8.1, the software RAID are called storage space, There are three different kinds of Storage Spaces: Simple spaces, Mirror spaces and Parity spaces:

    1.Simple spaces are designed for increased performance, but don't protect your files from drive failure by keeping multiple copies.

    2.Mirror spaces are designed for increased performance and protect your files from drive failure by keeping more than one copy. When a mirror space is formatted with the Resilient File System (ReFS), Windows will automatically maintain your data integrity, which makes your files even more resilient to drive failure.

    3.Parity spaces are designed for storage efficiency and protect your files from drive failure by keeping more than one copy.

    The detail can be found at: http://windows.microsoft.com/en-us/windows-8/storage-spaces-pools

    So, the read/write speed is related with Simple spaces, Mirror spaces is designed to protect files from system corrupt.

    Regards


    Wade Liu
    TechNet Community Support


    • Edited by Wade__Liu Tuesday, July 22, 2014 5:48 AM
    • Marked as answer by Michael_LS Tuesday, July 29, 2014 11:54 AM
    Tuesday, July 22, 2014 5:47 AM

All replies

  • Rromm

    Why would you want to use RAID in win 8 when it has built in storage to handle it?  RAID is a 20+ year old technology and there are so many better ways of keeping your data safe.  Read about storage spaces here


    Wanikiya and Dyami--Team Zigzag

    Thursday, July 17, 2014 1:23 PM
  • ziGZAg3143X

    isn't it the same thing because allows to mirror drives? can I boot OS from mirrored (there) partition?

    is there available to mirror disk to partition of another one? if yes – how to do what i've asked about?


    • Edited by rromm Thursday, July 17, 2014 1:57 PM
    Thursday, July 17, 2014 1:44 PM
  • Rromm

    Not the same thing.  I suggest you research RAID vs Storage spaces.  You have many questions that cant be answered in a single thread.

    Wiki http://en.wikipedia.org/wiki/RAID

    Standard RAID levels http://en.wikipedia.org/wiki/Standard_RAID_levels

    Storage spaces in win 8 http://helpdeskgeek.com/windows-8/create-raid-like-data-backup-using-storage-spaces-windows-8/


    Wanikiya and Dyami--Team Zigzag

    Thursday, July 17, 2014 2:37 PM
  • i have only few questions about your storage spaces.

    and till I get answers about them – i'm not interested.

    • Edited by rromm Thursday, July 17, 2014 4:15 PM
    Thursday, July 17, 2014 3:25 PM
  • Rromm

    Good Luck in your research


    Wanikiya and Dyami--Team Zigzag

    Thursday, July 17, 2014 3:30 PM
  • what research?

    waiting for answers.

    • Edited by rromm Friday, July 18, 2014 1:59 PM
    Thursday, July 17, 2014 3:40 PM
  • Hi,

    In Windows 8.1, the software RAID are called storage space, There are three different kinds of Storage Spaces: Simple spaces, Mirror spaces and Parity spaces:

    1.Simple spaces are designed for increased performance, but don't protect your files from drive failure by keeping multiple copies.

    2.Mirror spaces are designed for increased performance and protect your files from drive failure by keeping more than one copy. When a mirror space is formatted with the Resilient File System (ReFS), Windows will automatically maintain your data integrity, which makes your files even more resilient to drive failure.

    3.Parity spaces are designed for storage efficiency and protect your files from drive failure by keeping more than one copy.

    The detail can be found at: http://windows.microsoft.com/en-us/windows-8/storage-spaces-pools

    So, the read/write speed is related with Simple spaces, Mirror spaces is designed to protect files from system corrupt.

    Regards


    Wade Liu
    TechNet Community Support


    • Edited by Wade__Liu Tuesday, July 22, 2014 5:48 AM
    • Marked as answer by Michael_LS Tuesday, July 29, 2014 11:54 AM
    Tuesday, July 22, 2014 5:47 AM
  • still both questions not answered…
    Friday, August 1, 2014 7:18 AM
  • Rromm

    As I said close to 3 weeks ago GOOGLE IT.  There is no way we can (Or will) describe a complex process like RAID in a setting like this.

    I gave you 3 links above to get you started.  Time for you to invest some time of your own.


    Wanikiya and Dyami--Team Zigzag

    Friday, August 1, 2014 12:19 PM
  • My advice:  Buy very high quality drives, e.g., SSDs with 2 million hour MTBF ratings, do good backups, and don't fret over potential failures.

    Have you lost data from failed disks? 

    Do you do system image backups?

    Microsoft Storage Spaces are touted, but personally I've read enough horror stories about people losing all their data to want to wait and see on that tech.

     

    -Noel


    Detailed how-to in my eBooks:  

    Configure The Windows 7 "To Work" Options
    Configure The Windows 8 "To Work" Options

    Saturday, August 2, 2014 12:57 AM
  • Hi rrom,

    As said,the read/write speed is related with Simple spaces, Mirror spaces is designed to protect files from system corrupt, it not technically related to reading /writing speed. it is clearly stated in the article.

    Regards


    Wade Liu
    TechNet Community Support

    Wednesday, August 6, 2014 2:06 AM
  • but simple spaces is raid0 analog?

    I plan to mirror system SSD to HDD partition, how do you imagine raid0 speed there?

    if it would be 2 mirroring ssd – then would be double speed of ssd, but HDD is much slower.

    let's say ssd speed is 5byte/ms and hdd is 1b/ms, we read 4 bytes: odd byte reading from ssd takes 0.2 ms, while 2nd byte from hdd reads 5 times slower (1ms) – as I understand 3rd byte wont be readed till 2nd byte reads:

    so resulting speed is: slower (hdd) speed * 2 = 2bytes/ms, which is slower than just ssd speed. no raid0 speeds here.

    so we need to be able to disable reading from hdd and also use queue for writing to hdd for not delaying SSD. Is it possible in win8 to configure this? (If not – how to "add request"?)

    the point is we don't want to lose system if ssd crashes but we also don't want to downgrade performance.







    • Edited by rromm Thursday, February 19, 2015 5:23 AM
    Thursday, January 29, 2015 8:46 AM