After this change, user can query compression ratio on a per column
family basis with 'nodetool cfstats'.
look at 'nodetool cfstats' output:
./bin/nodetool cfstats ks.test5
Keyspace: ks
Read Count: 0
Read Latency: NaN ms.
Write Count: 0
Write Latency: NaN ms.
Pending Flushes: 0
Table: test5
SSTable count: 1
Space used (live): 4774
Space used (total): 4774
Space used by snapshots (total): 0
Off heap memory used (total): 131384
SSTable Compression Ratio: 0.833333
...
Fixes#636.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Message-Id: <a1bee5a23fe63787df3e387a88f2d216ba4a4134.1459802771.git.raphaelsc@scylladb.com>