I would like to see the state of the LSM-tree for a table in Cassandra.
Is there a way of viewing the number of SSTables, as well as their sizes, at any given time point, for a given table?
Are you looking for nodetool tablestats. In v2.x you can use it as nodetool cfstats.
You can know the number of sstables for a given column family and the total space occupied (not per sstable).
If you really want to know the size of each sstable, I recommend you can do a
df command on each of the nodes at the appropriate location.
Hope it helps!