Package oracle.nosql.driver

Interface StatsControl

  • public interface StatsControl

    This interface allows user to control the collection of driver statistics at runtime.

    The statistics data is collected for an interval of time. At the end of the interval, the stats data is logged in a specified JSON format that can be filtered and parsed. After the logging, the counters are cleared and collection of data resumes.

    Collection intervals are aligned to the top of the hour. This means first interval logs may contain stats for a shorter interval.

    Collection of stats are controlled by the following system properties:

    • -Dcom.oracle.nosql.sdk.nosqldriver.stats.profile=[none|regular|more|all] Specifies the stats profile: none - disabled, regular - per request: counters, errors, latencies, delays, retries more - stats above with 95th and 99th percentile latencies all - stats above with per query information.
    • -Dcom.oracle.nosql.sdk.nosqldriver.stats.interval=600 Interval in seconds to log the stats, by default is 10 minutes.
    • -Dcom.oracle.nosql.sdk.nosqldriver.stats.pretty-print=true Option to enable pretty printing of the JSON data, default value is false
    • -Dcom.oracle.nosql.sdk.nosqldriver.stats.enable-log=false Option to turn on logging automatically if stats are enabled, default value is true
    Statistics can also be enabled by using the API: NoSQLHandleConfig.setStatsProfile(StatsControl.Profile) or setProfile(StatsControl.Profile). At runtime stats collection can be enabled selectively by using start() and stop(). The following example shows how to use a stats handler and control the stats at runtime: 
         NoSQLHandleConfig config = new NoSQLHandleConfig( endpoint );
     config.setStatsProfile(StatsControl.Profile.REGULAR);
     config.setStatsInterval(600);
     config.setStatsPrettyPrint(false);
     config.setStatsHandler(
         new StatsControl.StatsHandler() {
             public void accept(MapValue jsonStats) {
                 System.out.println("!!! Got a stat: " + jsonStats);
             }
         });
     NoSQLHandle handle = NoSQLHandleFactory.createNoSQLHandle(config);

     StatsControl statsControl = handle.getStatsControl();

     //... application code without stats

     // enable observations
     statsControl.start();

     //... application code with REGULAR stats

     // For particular parts of code profile can be changed to collect more stats.
     statsControl.setProfile(StatsControl.Profile.ALL)
     //... more sensitive code with ALL stats
     statsControl.setProfile(StatsControl.Profile.REGULAR)

     //... application code with REGULAR stats

     // disable observations
     statsControl.stop();

     // ... application code without stats
     handle.close();

    For a detailed statistics log entries structure and values see oracle.nosql.driver

    Since:
    5.2.30

    • Method Detail

      • getInterval

        int getInterval()
        Returns the current collection interval. Default interval is 600 seconds, i.e. 10 min.
        Returns:
        the current collection interval

      • setProfile

        StatsControl setProfile​(StatsControl.Profile profile)
        Set the stats collection profile. Default profile is NONE.
        Parameters:
        profile - the stats collection profile
        Returns:
        this

      • getProfile

        StatsControl.Profile getProfile()
        Returns the collection profile. Default profile is NONE.
        Returns:
        the current profile

      • setPrettyPrint

        StatsControl setPrettyPrint​(boolean enablePrettyPrint)
        Enable JSON pretty print for easier human reading. Default is disabled.
        Parameters:
        enablePrettyPrint - flag to enable JSON pretty print
        Returns:
        this

      • getPrettyPrint

        boolean getPrettyPrint()
        Returns the current JSON pretty print flag. Default is disabled.
        Returns:
        the current JSON pretty print flag

      • getStatsHandler

        StatsControl.StatsHandler getStatsHandler()
        Returns the registered stats handler.
        Returns:
        the current handler, null if no handler has been registered.

      • start

        void start()
        Collection of stats is enabled only between start and stop or from the beginning if system property -Dcom.oracle.nosql.sdk.nosqldriver.stats.profile= is not "none".

      • stop

        void stop()
        Stops collection of stats.

      • isStarted

        boolean isStarted()
        Returns true if collection of stats is enabled, otherwise returns false.
        Returns:
        true if start() was called last, false otherwise.