Tomas Bodzar asked about RAM usage with Hammer and deduplication, pointing at this example that shows ZFS requiring… I’m not sure. Lots? Anyway, Matthew Dillon noted that offline deduplication in Hammer would use available RAM/swap for CRCs on all files, but only a limited subset for ‘live’ dedup. For a real-world example, Venkatesh Srinivas described deduplicating about 600G down to 400G, with a machine having only 256M of RAM. Yes, only 256M.
A running description of activity related to DragonFly BSD.
256M of RAM _and_ 32G of swapcache !