ICounters

Interface for performance counters that measure execution metrics.

Description

The ICounters interface defines the methods for performance counters that measure execution metrics.

Important points

  • The performance counters measure how code is performing; that is, how fast or slow is, how many transactions were performed, how many objects were stored, what was the latest transaction time and so on.
  • They are critical to monitor and improve performance, scalability and reliability of code in production.

Instance methods

beginTiming

Begins measurement of execution time interval. It returns CounterTiming object which has to be called at CounterTiming.endTiming to end the measurement and update the counter.

beginTiming(name: string): CounterTiming: void

  • name: string - a counter name of Interval type.
  • returns: CounterTiming - a callback object to end timing.

increment

Increments counter by a given value.

increment(name: string, value: number): void

  • name: string - a counter name of Increment type.
  • value: number - a value to add to the counter.

incrementOne

Increments counter by 1.

incrementOne(name: string): void

  • name: string - a counter name of Increment type.

last

Records the last calculated measurement value. Usually this method is used by metrics calculated externally.

last(name: string, value: number): void

  • name: string - a counter name of Last type.
  • value: number - a last value to record.

stats

Calculates min/average/max statistics based on the current and previous values.

stats(name: string, value: number): void

  • name: string - a counter name of Statistics type
  • value: number - a value to update statistics

timestamp

Records the given timestamp.

timestamp(name: string, value: Date): void

  • name: string - a counter name of Timestamp type.
  • value: Date - a timestamp to record.

timestampNow

Records the current time as a timestamp.

timestampNow(name: string): void

  • name: string - a counter name of Timestamp type.