It does the right thing - sstables sent to other nodes maintain their min/max timestamps so they’ll go to the right buckets
The bucket is selected using the timestamp of the newest cell in the sstable If you run a major compaction, you would undo the same bucketing Cleanup works by compacting an sstable with itself and excluding any partition no longer owned - it makes a new sstable, the original is deleted when the new one is finished -- Jeff Jirsa > On Nov 15, 2017, at 7:57 AM, Benjamin Heiskell <bheisk...@datto.com> wrote: > > Hello all, > > How does TWCS work when decommissioning a node? Does the data distribute > across the other nodes to the current time window's sstable (like > read-repairs)? Or will it compact into the sstables for the prior windows? If > that's how it works, how does it decide what sstable to compact with? E.g.., > if I ran a major compaction on one node (pushing everything into a few > sstables), then decommissioned it, what would you expect to see on other > nodes? Would the data distribute across all sstables based on the row's > timestamp? > > I'm also a little unclear on how cleanups work. If I run a nodetool cleanup, > will that actually re-write the old, but not completely expired sstables of > prior time windows? Or are those sstables truly immutable? > > I've read through the documentation > (http://cassandra.apache.org/doc/latest/operating/compaction.html#time-window-compactionstrategy) > and a few other resources > (http://thelastpickle.com/blog/2016/12/08/TWCS-part1.html), but I still don't > have a clear understanding of how it works. > > Any clarification would be greatly appreciated. Thanks! > Ben
