Friday saw the release of FreeNAS 8.3.0, which brings ZFS version 28 as a major new feature (compared to ZFS v15 in FreeNAS 8.2.x - this is no longer being developed, as the underlying FreeBSD 8.2 is not being developed further either). If you want to upgrade from FreeNAS 8.2.0-RELEASE-p1 does not need to reinstall the jail and plugins - only if the plugin jail is updated as well, a new installation of the plugins is required.
FreeNAS 8.3.0 or ZFS v28 supports "dedup", which requires a lot of RAM. According to the readme, the function for removing duplicate data requires 3 - 5 GB RAM per terabyte of disk space. If the RAM is not available, this can lead to performance problems and kernel panic, which cannot be prevented without removing the RAM. Private users should therefore rather not experiment with this option, unless they really know what effects it has.
You can download FreeNAS 8.3.0 directly from Sourcforge: FreeNAS Download Page.
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