mergerfs not distribute data evenly

  • EPMFS will use the existing path FIRST. Paths will be preserved if possible.

    And only then, if the same relative path happen to exist on more than one filesystem, the filesystem with the most free space (MFS) will be used.

    So if a folder didn't exist on any drive, it is added to the drive with the most free space. After that the path exists on one drive only and all subsequent files in that folder end up there.

    If you want files to be added to the filesystem with the most free space, and paths created as needed, then you should use just MFS, not EPMFS. That will spread the files all over your drives.

    Be smart - be lazy. Clone your rootfs.
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  • Yes. I think so. I haven't tried it yet.
    No. Not if you have good verified backups.

    But if you don't have good verified backups then all your files will be toast. Any change you make is almost guaranteed to cause catastrophic data loss. I almost promise 100%!

    Be smart - be lazy. Clone your rootfs.
    OMV 5: 9 x Odroid HC2 + 1 x Odroid HC1 + 1 x Raspberry Pi 4

  • What about using the mergerfs.balance script to even the spread of data across the drives?

    When I started with UFS/Snapraid I noticed uneven spread and this script ran for a few hours and evened disk usage up. Since then the disk use has been pretty even. My setup is MFS. This was on OMV v4.

    Naturally I had backups before I did this.


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  • I assume that new files will cause the same folders to be created on more drives, as new files are added and spread. The existing folders and files should remain where they are, unless you run the mergerfs.balance script.

    Changing from epmfs to mfs should be no different from creating a new mfs mergerfs pool from existing filesystems.

    Be sure to let us know how it works. I have not a lot of experience with mergerfs, but see a lot of potential in it.

    Be smart - be lazy. Clone your rootfs.
    OMV 5: 9 x Odroid HC2 + 1 x Odroid HC1 + 1 x Raspberry Pi 4

    Edited once, last by Adoby ().

  • The thread subject should be changed because SnapRAID has nothing to do with it.

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    Edited once, last by gderf ().

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