By periodic repair, I'll assume you mean "having to run repair every gc_grace period to make sure no deleted entries resurrect". With that assumption:
> 1. Regular values, no deletes, no overwrites, write heavy, ttl's to manage > size > Since 'repair within gc_grace' is about avoiding value that have been deleted to resurrect, if you do no delete nor overwrites, you're in no risk of that (and don't need to 'repair withing gc_grace'). > 2. Regular values, no deletes, some overwrites, read heavy (10 to 1), > ttl's to manage size > It depends a bit. In general, if you always set the exact same TTL on every insert (implying you always set a TTL), then you have nothing to worry about. If the TTL varies (of if you only set TTL some of the times), then you might still need to have some periodic repairs. That being said, if there is no deletes but only TTLs, then the TTL kind of lengthen the period at which you need to do repair: instead of needing to repair withing gc_grace, you only need to repair every gc_grace + min(TTL) (where min(TTL) is the smallest TTL you set on columns). 3. Counter values, no deletes, update heavy, rotation/truncation to manage > size > No deletes and no TTL implies that your fine (as in, there is no need for 'repair withing gc_grace'). -- Sylvain
