SStable count in Nodetool cfstats

Question

I recently started adding some data into cassandra for performance testing and also looking at the nodetool cfstats and the sstable count is still 0 even after inserting a lot of data. Even the space used live and total are still 0. Am I missing something?

Keyspace: perftest
Read Count: 0
Read Latency: NaN ms.
Write Count: 126056
Write Latency: 0.028907025449006793 ms.
Pending Tasks: 0
    Column Family: items
    SSTable count: 0
    Space used (live): 0
    Space used (total): 0
    SSTable Compression Ratio: 0.0
    Number of Keys (estimate): 0
    Memtable Columns Count: 252112
    Memtable Data Size: 214612059
    Memtable Switch Count: 0
    Read Count: 0
    Read Latency: NaN ms.
    Write Count: 126056
    Write Latency: 0.029 ms.
    Pending Tasks: 0
    Bloom Filter False Positives: 0
    Bloom Filter False Ratio: 0.00000
    Bloom Filter Space Used: 0
    Compacted row minimum size: 0
    Compacted row maximum size: 0
    Compacted row mean size: 0
    Average live cells per slice (last five minutes): 0.0
    Average tombstones per slice (last five minutes): 0.0

Answer 1

Your memtable data size is 214612059 (214 MB). This means the data isn't enough to have caused it to be flushed to disk yet. If you insert more it will be, or you can force a flush with nodetool flush.

The sizes listed are size on disk, so will be zero until a flush occurs.