Where is all of the space going on a drive added to server storage RRS feed

  • Question

  • I have Installed Vail and have setup an 75 gig drive for my storage volume at the moment simply for testing. Once I tell it to be part of the server storage and it goes through and makes all of the default shares it tells me that there is 66 gigs of total space and only 48 gigs free. Will this stay consistant? If I add more storage will I only get 64% of available space based upon the my current test of a 75 gig drive?  What is all this space used for you your guys doing some sort oof parity of comthing which needs 1/3rd of the total hard drive space?

    Keep in mind that I have only added the 1 drive for storage so there is no duplication happening.

    Tuesday, April 27, 2010 8:15 PM


  • Parity takes 1/9th of all space (we write 9 physical sectors of ECC'd data for each 8 logical sectors of data, which allows realtime correction of single and double bit flip errors even if duplication is not enabled), hence 75 GB --> 66 GB. We also pre-allocate 3 GBs per volume/share for MFT and other NTFS metadata files (those 3 GBs are not fully used though, so user data can be written into them if a need arises), so you see 18 GB allocated since we have six default shares. The 3 GB is a fixed number, so the relative impact of those will be greatly reduced if you use large drives (and we expect the majority of Vail servers to ship with 1TB+ drives).

    Bulat Shelepov, Test Lead (Drive Extender), Windows Home and Small Business Server Team
    Tuesday, April 27, 2010 8:48 PM