diff options
Diffstat (limited to 'kamon-core/src/main/scala/kamon/metric/instrument/MinMaxCounter.scala')
-rw-r--r-- | kamon-core/src/main/scala/kamon/metric/instrument/MinMaxCounter.scala | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/kamon-core/src/main/scala/kamon/metric/instrument/MinMaxCounter.scala b/kamon-core/src/main/scala/kamon/metric/instrument/MinMaxCounter.scala new file mode 100644 index 00000000..471e7bd4 --- /dev/null +++ b/kamon-core/src/main/scala/kamon/metric/instrument/MinMaxCounter.scala @@ -0,0 +1,116 @@ +package kamon.metric.instrument + +/* + * ========================================================================================= + * Copyright © 2013-2014 the kamon project <http://kamon.io/> + * + * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file + * except in compliance with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software distributed under the + * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, + * either express or implied. See the License for the specific language governing permissions + * and limitations under the License. + * ========================================================================================= + */ + +import java.lang.Math.abs +import java.util.concurrent.TimeUnit +import java.util.concurrent.atomic.AtomicReference +import akka.actor.{ ActorSystem, Cancellable } +import com.typesafe.config.Config +import jsr166e.LongMaxUpdater +import kamon.metric.{ Scale, MetricRecorder, CollectionContext } +import kamon.util.PaddedAtomicLong +import scala.concurrent.duration.FiniteDuration + +trait MinMaxCounter extends MetricRecorder { + override type SnapshotType = Histogram.Snapshot + + def increment(): Unit + def increment(times: Long): Unit + def decrement() + def decrement(times: Long) +} + +object MinMaxCounter { + + def apply(highestTrackableValue: Long, precision: Histogram.Precision, scale: Scale, refreshInterval: FiniteDuration, + system: ActorSystem): MinMaxCounter = { + + val underlyingHistogram = Histogram(highestTrackableValue, precision, scale) + val minMaxCounter = new PaddedMinMaxCounter(underlyingHistogram) + + val refreshValuesSchedule = system.scheduler.schedule(refreshInterval, refreshInterval) { + minMaxCounter.refreshValues() + }(system.dispatcher) // TODO: Move this to Kamon dispatchers + + minMaxCounter.refreshValuesSchedule.set(refreshValuesSchedule) + minMaxCounter + } + + def fromConfig(config: Config, system: ActorSystem): MinMaxCounter = { + import scala.concurrent.duration._ + + val highest = config.getLong("highest-trackable-value") + val significantDigits = config.getInt("significant-value-digits") + val refreshInterval = config.getDuration("refresh-interval", TimeUnit.MILLISECONDS) + + apply(highest, Histogram.Precision(significantDigits), Scale.Unit, refreshInterval.millis, system) + } +} + +class PaddedMinMaxCounter(underlyingHistogram: Histogram) extends MinMaxCounter { + private val min = new LongMaxUpdater + private val max = new LongMaxUpdater + private val sum = new PaddedAtomicLong + val refreshValuesSchedule = new AtomicReference[Cancellable]() + + min.update(0L) + max.update(0L) + + def increment(): Unit = increment(1L) + + def increment(times: Long): Unit = { + val currentValue = sum.addAndGet(times) + max.update(currentValue) + } + + def decrement(): Unit = decrement(1L) + + def decrement(times: Long): Unit = { + val currentValue = sum.addAndGet(-times) + min.update(-currentValue) + } + + def collect(context: CollectionContext): Histogram.Snapshot = { + refreshValues() + underlyingHistogram.collect(context) + } + + def cleanup: Unit = { + if (refreshValuesSchedule.get() != null) + refreshValuesSchedule.get().cancel() + } + + def refreshValues(): Unit = { + val currentValue = { + val value = sum.get() + if (value < 0) 0 else value + } + + val currentMin = { + val minAbs = abs(min.maxThenReset()) + if (minAbs <= currentValue) minAbs else 0 + } + + underlyingHistogram.record(currentValue) + underlyingHistogram.record(currentMin) + underlyingHistogram.record(max.maxThenReset()) + + max.update(currentValue) + min.update(-currentValue) + } +} |