diff --git a/priv/riak_kv.schema b/priv/riak_kv.schema index ebb54764b..1786a4e68 100644 --- a/priv/riak_kv.schema +++ b/priv/riak_kv.schema @@ -1471,23 +1471,30 @@ {commented, 900} ]}. -%% @doc Enable the `recalc` compaction strategy within the leveled backend in -%% riak. The default (when disabled) is `retain`, but this will leave -%% uncollected garbage within the, journal. -%% It is now recommended from Riak KV 2.9.2 to consider the `recalc` strategy. +%% @doc Enable the `recalc` compaction strategy +%% This is relevant only to the leveled backend. If disabled the `retain` +%% strategy will be used, but this will leave uncollected garbage within the +%% journal. +%% +%% The default `retain` strategy retains a history of key changes in the +%% journal, whereas the `recalc` strategy discards that history, but will redo +%% a diff_index_specs calculation when reloading each object. +%% +%% It is recommended to use the `recalc` strategy. +%% %% This strategy has a side effect of slower startups, and slower recovery %% from a wiped ledger - but it will not keep an overhead of garbage within %% the Journal. +%% %% It should be possible to move from `retain` to `recalc` via configuration %% change. However, it is not possible to switch from `recalc` back to -%% `retain`. This switch can only be made for new nodes receiving data -%% through riak transfers (not inheriting data on disk). -%% The default `retain` strategy retains a history of key changes in the -%% journal, whereas the `recalc` strategy discards that history, but will redo -%% a diff_index_specs calculation when reloading each object. +%% `retain` just by reverting the config. This switch can only be made for +%% new nodes receiving data through riak transfers (not inheriting data on +%% disk) - so a rolling `riak admin cluster replace` would be required to +%% revert to `retain`. {mapping, "leveled_reload_recalc", "riak_kv.leveled_reload_recalc", [ {datatype, {flag, enabled, disabled}}, - {default, disabled}, + {default, enabled}, {commented, enabled} ]}.