I use NTFS compression and with files this works without problems so long as there is space on the disk to uncompress the file. Drivepool also seems to be unconcerned when a file is compressed on one drive and uncompressed on a second drive.
However I have found a Windows API query on folder compression can give conflicting results when comparing the Compressed Attribute with the Compressed state. These should both be the same, but on folders on pooled drives this is not always the case. It is not a critical problem, but one which can impact changing the compressed status of folders. Unlike files, which are duplicated on two disks (or more if required), the folders, can exists on all disks. It would seem that updating the compressed status of a folder, is not being populated across all the drives on which the folder exists. My guess, and if this is correct, it could explain why some files are compressed on some drives, whilst the copy is uncompressed on another drive. I can visualize this could happen when files are moved between drives as part of the balance process, should the parent folder have a different compression state.
I would presume this would also apply to encrypted files.
Does should the Check Duplication Consistency also check if the folders have consistent attributes across all the copies of the folders?
Or I can script a utility to periodically scan the drives and use a majority vote to decide if a folder is compressed and set all the copies of the folders to have the same setting.
Is there any document which describes how the copies of the folders are created and managed on each drive in the pool?
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DavidUK
I use NTFS compression and with files this works without problems so long as there is space on the disk to uncompress the file. Drivepool also seems to be unconcerned when a file is compressed on one drive and uncompressed on a second drive.
However I have found a Windows API query on folder compression can give conflicting results when comparing the Compressed Attribute with the Compressed state. These should both be the same, but on folders on pooled drives this is not always the case. It is not a critical problem, but one which can impact changing the compressed status of folders. Unlike files, which are duplicated on two disks (or more if required), the folders, can exists on all disks. It would seem that updating the compressed status of a folder, is not being populated across all the drives on which the folder exists. My guess, and if this is correct, it could explain why some files are compressed on some drives, whilst the copy is uncompressed on another drive. I can visualize this could happen when files are moved between drives as part of the balance process, should the parent folder have a different compression state.
I would presume this would also apply to encrypted files.
Does should the Check Duplication Consistency also check if the folders have consistent attributes across all the copies of the folders?
Or I can script a utility to periodically scan the drives and use a majority vote to decide if a folder is compressed and set all the copies of the folders to have the same setting.
Is there any document which describes how the copies of the folders are created and managed on each drive in the pool?
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