Collecting system level diagnostics 

Collect system-wide performance information about a cluster. Enable and set the cql_system_info_options parameter in dse.yaml.

The following system level diagnostic tables collect system-wide performance information about a cluster:
  • key_cache

    Per node key cache metrics. Equivalent to nodetool info.

  • net_stats

    Per node network information. Equivalent to nodetool netstats.

  • thread_pool

    Per node thread pool active/blocked/pending/completed statistics by pool. Equivalent to nodetool tpstats.

  • thread_pool_messages

    Per node counts of dropped messages by message type. Equivalent to nodetool tpstats.

Procedure

To collect system level data:

  1. Edit the dse.yaml file.
    The location of the dse.yaml file depends on the type of installation:
    Installer-Services /etc/dse/dse.yaml
    Package installations /etc/dse/dse.yaml
    Installer-No Services install_location/resources/dse/conf/dse.yaml
    Tarball installations install_location/resources/dse/conf/dse.yaml
  2. In the dse.yaml file, set the enabled option for cql_system_info_options to true.
    # CQL system info tables settings
    cql_system_info_options:
        enabled: true
        refresh_rate_ms: 10000
  3. (Optional) To control how often the statistics are refreshed, increase or decrease the refresh_rate_ms parameter.

    The refresh_rate_ms specifies the length of the sampling period, that is, the frequency with which this data is updated.