Hi Carl, The ‘repair’ is for data reads. Compaction will take care of the expired data.
The fact a repair runs long makes me think the nodes receive unbalanced amounts of writes rather. Regards, Arthur From: Carl Lerche Sent: Thursday, August 01, 2013 12:35 PM To: user@cassandra.apache.org Subject: How often to run `nodetool repair` Hello, I read in the docs that `nodetool repair` should be regularly run unless no delete is ever performed. In my app, I never delete, but I heavily use the ttl feature. Should repair still be run regularly? Also, does repair take less time if it is run regularly? If not, is there a way to incrementally run it? It seems that when I do run repair, it takes a long time and causes high amounts CPU usage and iowait. Thoughts? Thanks, Carl