SizeTieredCompactionStrategy only compacts sstables that are a similar size (by default, they basically need to be within 50% of each other). Perhaps your first SSTable was very large or small compared to the others?
On Mon, Oct 7, 2013 at 8:06 PM, Sameer Farooqui <[email protected]>wrote: > Hi, > > I have a fresh 1-node C* 2.0 install with a demo keyspace created with the > SizeTiered compaction strategy. > > I've noticed that in the beginning this keyspace has just one SSTable: > demodb-users-jb-1-Data.db > > But as I add more data to the table and do some flushes, the # of SSTables > builds up. After I have a handful of SSTables, I trigger a flush using > 'nodetool flush demodb users', but then not ALL of the SSTables get > compacted. > > I've noticed that the 1st SSTable remains the same and doesn't disappear > after the compaction, but the latter SSTables do get compacted into one new > Data file. > > Is there a reason why the first SSTable is special and it is not > disappearing after compaction? > > Also, I think I noticed that if I wait a few days and run another > compaction, then that 1st SSTable does not compacted (and it disappears). > > Can someone help explain why the 1st SSTable behaves this way? > -- Tyler Hobbs DataStax <http://datastax.com/>
