Enforce monotonicity for IncrementableMetrics

This change enforces that IncrementableMetrics should only monotonically
increase in value, and adds a new increment() method to increment by one, which is slightly faster than incrementBy (due to a lack of non-negative checking) in the common case that the counter should only be incremented by one.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=130578421
This commit is contained in:
shikhman 2016-08-17 16:35:08 -07:00 committed by Ben McIlwain
parent 01e38790fd
commit f10a7d8fb0
4 changed files with 33 additions and 9 deletions

View file

@ -49,17 +49,25 @@ public final class Counter extends AbstractMetric<Long>
}
@VisibleForTesting
void incrementBy(Number offset, ImmutableList<String> labelValues) {
values.addAndGet(labelValues, offset.longValue());
void incrementBy(long offset, ImmutableList<String> labelValues) {
values.addAndGet(labelValues, offset);
}
@Override
public final void incrementBy(long offset, String... labelValues) {
checkArgument(labelValues.length == this.getMetricSchema().labels().size(), LABEL_COUNT_ERROR);
checkArgument(offset >= 0, "The offset provided must be non-negative");
incrementBy(offset, ImmutableList.copyOf(labelValues));
}
@Override
public final void increment(String... labelValues) {
checkArgument(labelValues.length == this.getMetricSchema().labels().size(), LABEL_COUNT_ERROR);
incrementBy(1L, ImmutableList.copyOf(labelValues));
}
/**
* Returns a snapshot of the metric's values. The timestamp of each {@link MetricPoint} will be
* the last modification time for that tuple of label values.