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Impact of changing cache and compression settings on existing pools?

User_ZLVRK Member Posts: 1 Green Ribbon


I currently have an existing pool on ZFS storage appliance that is already in use and has a bunch of virtual machines. The virtual machines are running very slow so I have researched some tips and want to try to change some settings to see the impact. As described here:

Currently the pool is set to cache all data and metadata and no compression algorithm is used.

My question is if I change these settings to metadata and compression, will this have a risk of losing my data and crashing of a currently running system. My guess that it will, but maybe I am wrong.

So I will be glad to hear from you how safe this is because I have no test pools to use.



  • Nik
    Nik Blocked Member Posts: 2,879 Bronze Crown


    1. Provided docs - for ZFS on Solaris 10.

    ZFS-SA based on Solaris, but use another tool for manage. Do not use direct "shell" for tuning pools.

    Provided docs direct say that allow tune existing pool.

    "When these properties are set on existing file systems, only new I/O is cache based on the values of these properties."

    Docs provide steps for new created pool and already created FS.

    Not clear what exactly You plan do.

    Changing compression options do not touch data that already present on array. This data should be rewrite for apply new settings.

    Regards, Nik.