Is there any negative performance outcomes by Enabling Dedup on Main Z-Pool?

[KevDog]

Part of my FreeNas hosts an instance of Nextcloud for local users. Perusing their forums, a user suggesting enabling Dedup on the zpool. I checked and this is not enabled by default. Are their any negatives about enabling dedup on the main z-pool? Could it be reversed if later I turned it off? User felt it was a way to save storage space if users were possibly uploading copies of the same files or pictures.

 

[anmnz]

See the User Guide section on dedup for some answers to these questions. https://www.ixsystems.com/documentation/freenas/11.2-U6/storage.html#deduplication

The very high RAM requirement for ZFS dedup means it's almost always best avoided. I think people would want to see a whole lot of detail on your system, how it's used and what the data sizes are before recommending anything different.

 

[KevDog]

Thanks -- that's very informative. You answered by question. 5Gb of RAM per 1Tb of storage --- not for me.