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Kramer
Mod
join:2000-08-03
Richmond, VA

Kramer

Mod

[WIN8] Storage Spaces

While much discussion of Windows 8 continues to wrap around the UI, I thought I would change the subject just a little and describe what I have found to be a really nice feature. It is called "Storage Spaces." I'm not going to get into a long discussion of how it works, but would recommend this excellent article »www.pcpro.co.uk/features ··· to-guide from PCPRO by Darien Graham-Smith. Let me just describe how I use the feature and the few tests I have done.

I have always been hesitant to use External hard drives for anything important. I have had so many of them go on the blink, that the thought of putting anything important on them is something I quickly reconsider. Not any more. At least as long as you are willing to have at least 2 drives to do the job of one. Redundancy is part of what Storage Spaces is all about. Now if I want to use an external drive for storage, I can do so with a fairly high degree of safety. Before implementing storage spaces, my system was configured with two 1TB hard drives mirrored using my Intel based motherboard's RAID facilities. The Intel RAID is quite good and I use it on a lot of systems I recommend. Its biggest drawback is what happens when your system is shut down abruptly. With my 1TB drives, you are very likely to embark on a RAID rebuild which slows your system down to a crawl for 3-4 hours. The other drawback is that you are only able to create RAID volumes that are attached the the motherboard's Intel hard drive controller. This would exclude drives attached any controllers using a third party chipset like like a lot of motherboard manufacturers like to include, but more importantly it completely excludes USB drives. While I believe eSATA drives can be RAIDed using the Intel chipset, I'm not comfortable setting up a RAID relationship between an attached external device and an internal one. A lot could go wrong.

I have one external 1TB hard drive that I really had not used for anything. I also had a 1TB internal hard drive that was freed up when a guy a street behind my house got electrocuted and fried my file server. I set up a mirrored relationship between the external and the internal. Storage Spaces is not RAID, but for my purposes that is a benefit. One of my first experiments was to disconnect the external drive from the system and then copy a file to the remaining internal drive of the set. Then I re-attached the external drive and watched the rebuild process. As I said before using my built in Intel RAID the rebuild would have taken hours and made my system close to unusable during that time. Using "Storage Spaces" the rebuild took a matter of seconds. All the system had to do was copy over the missing file data. This is cool! The bad news is pretty obvious. The speed of your RAID-like set is limited to the slowest drive in the set. I also think Microsoft could do more to notify you of a failure. You are notified, but the notification could easily be missed. Finally you can't make your system volume any part of a Storage Space.

Questions remain:
One of the questions I have yet to answer is how Microsoft handles data mismatches. How is the drive with the newest data determined and does that really matter? What if there is new data on both hard drives? As best as I have been able to figure, Intel handles it by simply dating the last access of the HD. If you remove a drive from the array and then start up the system, the remaining drive is the template for the missing drive when it is replaced. You can externally add data to that missing drive, but when you place it back into the array, it is going to get over-written if the date of last access on the remaining drive is newer than that of the removed drive. I get into this mess all the time when removing malware from RAIDed systems. In a mirrored situation, it is a heck of lot easier to just remove one of the drives, so you are not dealing with ultra-slow systems during repair as the malware infections often result in forced shutdowns and broken mirror sets. Should you totally screw up the remaining drive, you always have the other one as a fallback. When you are done removing the malware, you replace the missing part of the mirror set, knowing that it will be over-written with the work you have done.

Here is where I am going with this. Suppose Microsoft made this system really amazing and made it so data is essentially synchronized between the two drives on a rebuild. I have a bit of hope they did this by watching that earlier rebuild and the way it happened. Wouldn't it be nice if files that don't exist on one drive are copied from the other in both directions. Files which have conflict are survived by the newest version. Dreaming right? Let me give you an example of an application. Suppose I take my external drive with me when I go on vacation. Depending on the length and place of the vacation I might want to put up to 50GB of photo and video data on that drive. Then if all works as I would like it, when I get home I simply re-attach the drive to my system and it is immediately copied back to the remaining internal drive and my data is in a redundant state. A lot could go wrong with this. Suppose Microsoft looks at the remaining internal drive as the most modern version of my data, the way Intel would. That would erase everything I have put on the external drive. Without an additional backup, I would lose my vacation photos and videos and be quite sad. I simply do not know how this data replication works and I need to experiment some more. Does anyone have any experience with this? I have no way to test this at present the way I would like. Storage Spaces are only visible by Windows 8 systems. My only Windows 8 system is my desktop. If I were to detach my external drive and write data to it, and then re-attach it, would the data remain or be erased? What if I added data to both drives independent of the the mirror set. Would that data be preserved on both? I could simulate this by detaching the Internal and external drives at various times, but it would be a lot easier and safer if I had another WIN8 system. I could kick myself in the you know where, for not taking advantage of the low MS price on my laptop when it was available.

I'm going to hop on the soapbox for a minute here. A lot of talk in this forum lately seems to judge Windows 8 simply on the basis of the UI and looks at nothing else the OS offers. "Storage Spaces" is just one of many nice new features that some of you who have not upgraded, might benefit from. The new UI of Windows 8 is completely ignorable with 3rd party software. You shouldn't rule out upgrading simply because of the UI. I agree MS botched it for desktop and conventional laptop users, but that is easily remedied. Don't avoid WIN8 simply because of the UI as that would be a mistake.

urbanriot
Premium Member
join:2004-10-18
Canada

urbanriot

Premium Member

Basically, if I read your post accurately, they took the JBOD functionality from Windows Home Server and gave the ability to use mirroring or parity... and call it 'spaces'.

This 6 minute video might make it easier for people to decipher or see for themselves - »technet.microsoft.com/en ··· 996.aspx

Still a little entirely unsure about this virtual space, this 'thin provisioning'. "How can you have 20 TB of space with 1 TB of physical storage? Thin provisioning!" not exactly an explanation.

Kramer
Mod
join:2000-08-03
Richmond, VA

Kramer

Mod

Yes, I am a bit unclear on that too. My understanding is the space is reserved for future storage upgrades. I like the demo with the 5 disks.

Octavean
MVM
join:2001-03-31
New York, NY

Octavean to Kramer

MVM

to Kramer
When Windows 7 was released I upgraded without really needing many of its features. I was glad to have some of these features later like TRIM support for SSD units.

I have not yet tried storage Spaces with Windows 8 but it is something I would like to try. My newer systems only have SSD units and no conventional HDDs but I would like to know if using Storage Spaces with SSD units would still allow for TRIM support while making the drives look like one large single SSD. Naturally the OS drive would be excluded from the pool. I hear Intel had added support for TRIM for RAID 0 arrays on Z77 chipset based systems with X79 support still pending,...

Having said that, I have used Storage Spaces in a recent Windows Server 2012 Essentials build. With the following Drives:

WD 2TB OS HDD
WD 3TB Storage Spaces Pool (3x)
Seagate 3TB Storage Spaces Pool (2x)

Totaling ~15TB not including the 2TB OS drive.

I also have a 4TB Seagate HDD I want to add to the pool when I get back.

I started the pool with three WD 3TB HDDs and added the rest individually as I installed them. Adding them in this way I found that Windows Server 2012 automatically configured the added drives for redundancy. This left me thinking momentarily "where is the storage space I just added?" and wasn't what I wanted. It was easy enough to add the storage to the pool the way I wanted it though.