Hello all, We are running c* version 2.0.15. We have 5 nodes with RF=3. We are using DTCS and on all inserts we have a TTL of 30 days. We have no deletes.We just have one CF. When i run nodetool repair on a node i notice a lot of extra sst tables created, this I think is due to the fact that its trying to reconcile the correct values across different nodes. What i am trying to figure out now is how will this affect the performance after the ttl is reached for rows. As far as i understood from Spotify DTCS <https://labs.spotify.com/tag/dtcs/> it looks like DTCS will drop the whole SST table once the ttl is reached as it compacts data which are inserted around the same time into same SST table. Now when repair happens we have these new SST Tables which are earlier in the timeline and hence will have tombstones alive for sometime.
for ex if the machine is up for 2 weeks and i run repair now for the first time then the new sst tables might have data which is from anywhere in the previous weeks and hence even though the SST tables created during week 1 will get dropped off in the starting of 5th Week because of repair there will additional SST tables which will have tombstones till they reach their eventual drop state a few weeks later. Am i thinking correct ? This means that we might still have lot of tombstones lying around as compaction is less frequent for older tables ? thanks anishek