stormpot

Interface MetricsRecorder

public interface MetricsRecorder

A MetricsRecorder implementation supplies the pool with the ability to record and report operational metrics. Many of the methods of the ManagedPool interface relies on a MetricsRecorder being configured for the given pool. Stormpot provides no default implementation of this interface, so by default many of the metrics reporting methods of the ManagedPool interfaces will return Double.NaN.

Note	that implementations of this class must be thread-safe!

Here’s an example implementation based on Coda Hale’s Metrics library:

package stormpot.examples;

import com.codahale.metrics.Histogram;
import com.codahale.metrics.MetricRegistry;
import stormpot.MetricsRecorder;

public class CodaHaleMetricsRecorder implements MetricsRecorder {
  private final Histogram allocationLatency;
  private final Histogram allocationFailureLatency;
  private final Histogram deallocationLatency;
  private final Histogram reallocationLatency;
  private final Histogram reallocationFailureLatency;
  private final Histogram objectLifetime;

  public CodaHaleMetricsRecorder(String baseName, MetricRegistry registry) {
    allocationLatency = registry.histogram(baseName + ".allocationLatency");
    allocationFailureLatency = registry.histogram(baseName + ".allocationFailureLatency");
    deallocationLatency = registry.histogram(baseName + ".deallocationLatency");
    reallocationLatency = registry.histogram(baseName + ".reallocationLatency");
    reallocationFailureLatency = registry.histogram(baseName + ".reallocationFailureLatency");
    objectLifetime = registry.histogram(baseName + ".objectLifetime");
  }

  @Override
  public void recordAllocationLatencySampleMillis(long milliseconds) {
    allocationLatency.update(milliseconds);
  }

  @Override
  public void recordAllocationFailureLatencySampleMillis(long milliseconds) {
    allocationFailureLatency.update(milliseconds);
  }

  @Override
  public void recordDeallocationLatencySampleMillis(long milliseconds) {
    deallocationLatency.update(milliseconds);
  }

  @Override
  public void recordReallocationLatencySampleMillis(long milliseconds) {
    reallocationLatency.update(milliseconds);
  }

  @Override
  public void recordReallocationFailureLatencySampleMillis(long milliseconds) {
    reallocationFailureLatency.update(milliseconds);
  }

  @Override
  public void recordObjectLifetimeSampleMillis(long milliseconds) {
    objectLifetime.update(milliseconds);
  }

  @Override
  public double getAllocationLatencyPercentile(double percentile) {
    return allocationLatency.getSnapshot().getValue(percentile);
  }

  @Override
  public double getAllocationFailureLatencyPercentile(double percentile) {
    return allocationFailureLatency.getSnapshot().getValue(percentile);
  }

  @Override
  public double getDeallocationLatencyPercentile(double percentile) {
    return deallocationLatency.getSnapshot().getValue(percentile);
  }

  @Override
  public double getReallocationLatencyPercentile(double percentile) {
    return reallocationLatency.getSnapshot().getValue(percentile);
  }

  @Override
  public double getReallocationFailurePercentile(double percentile) {
    return reallocationFailureLatency.getSnapshot().getValue(percentile);
  }

  @Override
  public double getObjectLifetimePercentile(double percentile) {
    return objectLifetime.getSnapshot().getValue(percentile);
  }
}

Since:

2.3

Method Summary

Methods

Modifier and Type	Method and Description
double	getAllocationFailureLatencyPercentile(double percentile) Get the approximate latency value, in milliseconds, for failed allocation latencies within the given percentile/quantile of what has been recorded so far.
double	getAllocationLatencyPercentile(double percentile) Get the approximate Poolable object allocation latency value, in milliseconds, of the given percentile/quantile of the values recorded so far.
double	getDeallocationLatencyPercentile(double percentile) Get the approximate latency value, in milliseconds, for deallocation latencies within the given percentile/quantile of what has been recorded so far.
double	getObjectLifetimePercentile(double percentile) Get the approximate object lifetime, in milliseconds, for the given percentile/quantile.
double	getReallocationFailurePercentile(double percentile) Get the approximate latency value, in milliseconds, for failed reallocation latencies within the given percentile/quantile of what has been recorded so far.
double	getReallocationLatencyPercentile(double percentile) Get the approximate latency value, in milliseconds, for reallocation latencies within the given percentile/quantile of what has been recorded so far.
void	recordAllocationFailureLatencySampleMillis(long milliseconds) Record a latency sample of a failed allocation, in milliseconds.
void	recordAllocationLatencySampleMillis(long milliseconds) Record a latency sample of a successful allocation, in milliseconds.
void	recordDeallocationLatencySampleMillis(long milliseconds) Record a latency sample of a deallocation, in milliseconds.
void	recordObjectLifetimeSampleMillis(long milliseconds) Record an object lifetime sample, in milliseconds.
void	recordReallocationFailureLatencySampleMillis(long milliseconds) Record a latency sample of a failed reallocation, in milliseconds.
void	recordReallocationLatencySampleMillis(long milliseconds) Record a latency sample of a successful reallocation, in milliseconds.

Method Detail

recordAllocationLatencySampleMillis

void recordAllocationLatencySampleMillis(long milliseconds)

Record a latency sample of a successful allocation, in milliseconds. This is the time it took for a call to Allocator.allocate(Slot) to return a useable object.

Parameters:

milliseconds - How many milliseconds it took to successfully allocate an object.

recordAllocationFailureLatencySampleMillis

void recordAllocationFailureLatencySampleMillis(long milliseconds)

Record a latency sample of a failed allocation, in milliseconds. This is the time it took for a call to Allocator.allocate(Slot) to throw an exception or return null.

Parameters:

milliseconds - How many milliseconds transpired before the allocation failed.

recordDeallocationLatencySampleMillis

void recordDeallocationLatencySampleMillis(long milliseconds)

Record a latency sample of a deallocation, in milliseconds. This is the time it took to complete a call to Allocator.deallocate(Poolable).

Parameters:

milliseconds - How many milliseconds to took to deallocate an object.

recordReallocationLatencySampleMillis

void recordReallocationLatencySampleMillis(long milliseconds)

Record a latency sample of a successful reallocation, in milliseconds. This is the time it took for a call to Reallocator.reallocate(Slot, Poolable) to return a useable object.

Parameters:

milliseconds - How many milliseconds it took to successfully reallocate an object.

recordReallocationFailureLatencySampleMillis

void recordReallocationFailureLatencySampleMillis(long milliseconds)

Record a latency sample of a failed reallocation, in milliseconds. This is the time it took for a call to Reallocator.reallocate(Slot, Poolable) to throw an exception or return null.

Parameters:

milliseconds - How many milliseconds transpired before the reallocation failed.

recordObjectLifetimeSampleMillis

void recordObjectLifetimeSampleMillis(long milliseconds)

Record an object lifetime sample, in milliseconds. This is the time that transpired from an object was allocated with Allocator.allocate(Slot), till it was deallocated with Allocator.deallocate(Poolable).

Parameters:

milliseconds - How many milliseconds a Poolable object was in circulation; from it was created, till it was deallocated.

getAllocationLatencyPercentile

double getAllocationLatencyPercentile(double percentile)

Get the approximate Poolable object allocation latency value, in milliseconds, of the given percentile/quantile of the values recorded so far.

A percentile, or quantile, is a value between 0.0 and 1.0, both inclusive, which represents a percentage of the recorded samples. In other words, given a percentile, the returned value will be the latency in milliseconds, that the given percent of samples is less than or equal to. For instance, if given the percentile 0.9 returns 120, then 90% of all recorded latency samples will be less than or equal to 120 milliseconds.

Note: Implementers should strive to return Double.NaN as a sentinel value, if they do not support recording of the allocation latencies and/or returning a specific percentile of such recordings.

Parameters:

percentile - The percentile/quantile to get a value for.

Returns:

The latency value in milliseconds for the given percentile/quantile.

getAllocationFailureLatencyPercentile

double getAllocationFailureLatencyPercentile(double percentile)

Get the approximate latency value, in milliseconds, for failed allocation latencies within the given percentile/quantile of what has been recorded so far.

A percentile, or quantile, is a value between 0.0 and 1.0, both inclusive, which represents a percentage of the recorded samples. In other words, given a percentile, the returned value will be the latency in milliseconds, that the given percent of samples is less than or equal to. For instance, if given the percentile 0.9 returns 120, then 90% of all recorded latency samples will be less than or equal to 120 milliseconds.

Note: Implementers should strive to return Double.NaN as a sentinel value, if they do not support recording of the allocation latencies and/or returning a specific percentile of such recordings.

Parameters:

percentile - The percentile/quantile to get a value for.

Returns:

The latency value in milliseconds for the given percentile/quantile.

getDeallocationLatencyPercentile

double getDeallocationLatencyPercentile(double percentile)

Get the approximate latency value, in milliseconds, for deallocation latencies within the given percentile/quantile of what has been recorded so far.

A percentile, or quantile, is a value between 0.0 and 1.0, both inclusive, which represents a percentage of the recorded samples. In other words, given a percentile, the returned value will be the latency in milliseconds, that the given percent of samples is less than or equal to. For instance, if given the percentile 0.9 returns 120, then 90% of all recorded latency samples will be less than or equal to 120 milliseconds.

Note: Implementers should strive to return Double.NaN as a sentinel value, if they do not support recording of the allocation latencies and/or returning a specific percentile of such recordings.

Parameters:

percentile - The percentile/quantile to get a value for.

Returns:

The latency value in milliseconds for the given percentile/quantile.

getReallocationLatencyPercentile

double getReallocationLatencyPercentile(double percentile)

Get the approximate latency value, in milliseconds, for reallocation latencies within the given percentile/quantile of what has been recorded so far.

A percentile, or quantile, is a value between 0.0 and 1.0, both inclusive, which represents a percentage of the recorded samples. In other words, given a percentile, the returned value will be the latency in milliseconds, that the given percent of samples is less than or equal to. For instance, if given the percentile 0.9 returns 120, then 90% of all recorded latency samples will be less than or equal to 120 milliseconds.

Note: Implementers should strive to return Double.NaN as a sentinel value, if they do not support recording of the allocation latencies and/or returning a specific percentile of such recordings.

Parameters:

percentile - The percentile/quantile to get a value for.

Returns:

The latency value in milliseconds for the given percentile/quantile.

getReallocationFailurePercentile

double getReallocationFailurePercentile(double percentile)

Get the approximate latency value, in milliseconds, for failed reallocation latencies within the given percentile/quantile of what has been recorded so far.

A percentile, or quantile, is a value between 0.0 and 1.0, both inclusive, which represents a percentage of the recorded samples. In other words, given a percentile, the returned value will be the latency in milliseconds, that the given percent of samples is less than or equal to. For instance, if given the percentile 0.9 returns 120, then 90% of all recorded latency samples will be less than or equal to 120 milliseconds.

Note: Implementers should strive to return Double.NaN as a sentinel value, if they do not support recording of the allocation latencies and/or returning a specific percentile of such recordings.

Parameters:

percentile - The percentile/quantile to get a value for.

Returns:

The latency value in milliseconds for the given percentile/quantile.

getObjectLifetimePercentile

double getObjectLifetimePercentile(double percentile)

Get the approximate object lifetime, in milliseconds, for the given percentile/quantile.

A percentile, or quantile, is a value between 0.0 and 1.0, both inclusive, which represents a percentage of the recorded samples. In other words, given a percentile, the returned value will be the latency in milliseconds, that the given percent of samples is less than or equal to. For instance, if given the percentile 0.9 returns 120, then 90% of all recorded latency samples will be less than or equal to 120 milliseconds.

Note: Implementers should strive to return Double.NaN as a sentinel value, if they do not support recording of the allocation latencies and/or returning a specific percentile of such recordings.

Parameters:

percentile - The percentile/quantile to get a value for.

Returns:

The latency value in milliseconds for the given percentile/quantile.