Last week we reported that a native ZFS implementation for Linux is soon being released that is based upon the work by Lawrence Livermore National Laboratory to bring Sun's ZFS file-system to Linux as a CDDL-licensed kernel module.
As said though in that article, there is already a ZFS module for FUSE (File-system in User-space) that is already available and with it not living in the GPL-land of the Linux kernel, it is legally allowed, but it does not come without some performance overhead. Over the weekend though there's been some discussions in the related forum thread and elsewhere about the dependability of ZFS-FUSE and what the level of impact on using FUSE really amounts to in real-world usage. We have tested the ZFS-FUSE -- both the latest stable and Git snapshots -- and have compared this alternate ZFS Linux implementation to that of the native EXT4 and Btrfs.
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