SLING-7222 - Too frequent samples
Apply patch from Marcel
diff --git a/src/main/java/org/apache/sling/commons/metrics/rrd4j/impl/RRD4JReporter.java b/src/main/java/org/apache/sling/commons/metrics/rrd4j/impl/RRD4JReporter.java
index a0caef4..40dbd7c 100644
--- a/src/main/java/org/apache/sling/commons/metrics/rrd4j/impl/RRD4JReporter.java
+++ b/src/main/java/org/apache/sling/commons/metrics/rrd4j/impl/RRD4JReporter.java
@@ -62,6 +62,7 @@
private final Map<String, Integer> dictionary = new HashMap<>();
private final RrdDb rrdDB;
+ private long lastSampleTime;
static Builder forRegistry(MetricRegistry metricRegistry) {
return new Builder(metricRegistry);
@@ -212,11 +213,16 @@
SortedMap<String, Histogram> histograms,
SortedMap<String, Meter> meters,
SortedMap<String, Timer> timers) {
+ long sampleTime = System.currentTimeMillis() / 1000;
+ if (sampleTime <= lastSampleTime) {
+ // sample at most once a second
+ return;
+ }
long time = System.nanoTime();
int total = gauges.size() + counters.size() + histograms.size() + meters.size() + timers.size();
int reported = 0;
try {
- Sample sample = rrdDB.createSample(System.currentTimeMillis() / 1000);
+ Sample sample = rrdDB.createSample(sampleTime);
for (Map.Entry<String, Gauge> entry : gauges.entrySet()) {
reported += update(sample, entry.getKey(), entry.getValue());
}
@@ -240,6 +246,7 @@
} catch (IOException e) {
LOGGER.warn("Unable to write sample to RRD", e);
} finally {
+ lastSampleTime = sampleTime;
time = System.nanoTime() - time;
LOGGER.debug("{} out of {} metrics reported in {} \u03bcs",
reported, total, TimeUnit.NANOSECONDS.toMicros(time));
diff --git a/src/test/java/org/apache/sling/commons/metrics/rrd4j/impl/RRD4JReporterTest.java b/src/test/java/org/apache/sling/commons/metrics/rrd4j/impl/RRD4JReporterTest.java
new file mode 100644
index 0000000..922500a
--- /dev/null
+++ b/src/test/java/org/apache/sling/commons/metrics/rrd4j/impl/RRD4JReporterTest.java
@@ -0,0 +1,76 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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.
+ */
+package org.apache.sling.commons.metrics.rrd4j.impl;
+
+import java.io.File;
+import java.io.IOException;
+
+import com.codahale.metrics.Gauge;
+import com.codahale.metrics.MetricRegistry;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+public class RRD4JReporterTest {
+
+ private static final File RRD = new File(new File("target", "metrics"), "metrics.rrd");
+
+ private MetricRegistry registry = new MetricRegistry();
+ private RRD4JReporter reporter;
+
+ @Before
+ public void before() throws IOException {
+ RRD.delete();
+ registry.register("myMetric", new TestGauge(42));
+ reporter = RRD4JReporter.forRegistry(registry)
+ .withPath(RRD)
+ .withArchives(new String[]{"RRA:AVERAGE:0.5:1:60"})
+ .withDatasources(new String[]{"DS:sling_myMetric:GAUGE:300:0:U"})
+ .withStep(1)
+ .build();
+ }
+
+ @After
+ public void after() {
+ reporter.close();
+ RRD.delete();
+ }
+
+ @Test
+ public void tooFrequentSamples() {
+ reporter.report();
+ reporter.report();
+ }
+
+ private static final class TestGauge implements Gauge<Long> {
+
+ private final long value;
+
+ TestGauge(long value) {
+ this.value = value;
+ }
+
+ @Override
+ public Long getValue() {
+ return value;
+ }
+ }
+}
+
