mjsax commented on a change in pull request #8697:
URL: https://github.com/apache/kafka/pull/8697#discussion_r429499547
##########
File path:
clients/src/test/java/org/apache/kafka/common/metrics/MetricsTest.java
##########
@@ -492,6 +493,52 @@ public void testPercentiles() {
assertEquals(75, (Double) p75.metricValue(), 1.0);
}
+ @Test
+ public void testPercentilesWithRandomNumbersAndLinearBucketing() {
+ long seed = new Random().nextLong();
+ int sizeInBytes = 1000 * 1000; // 1MB
+ long maximumValue = 1000 * 24 * 60 * 60 * 1000L; // if values are ms,
max is 1000 days
+
+ try {
+ Random prng = new Random(seed);
+ int numberOfValues = 5000 + prng.nextInt(10_000); // ranges is
[5000, 15000]
+
+ Percentiles percs = new Percentiles(sizeInBytes,
+ maximumValue,
+ BucketSizing.LINEAR,
+ new
Percentile(metrics.metricName("test.p90", "grp1"), 90),
+ new
Percentile(metrics.metricName("test.p99", "grp1"), 99));
+ MetricConfig config = new
MetricConfig().eventWindow(50).samples(2);
+ Sensor sensor = metrics.sensor("test", config);
+ sensor.add(percs);
+ Metric p90 =
this.metrics.metrics().get(metrics.metricName("test.p90", "grp1"));
+ Metric p99 =
this.metrics.metrics().get(metrics.metricName("test.p99", "grp1"));
+
+ final List<Long> values = new ArrayList<>(numberOfValues);
+ // record two windows worth of sequential values
+ for (int i = 0; i < numberOfValues; ++i) {
+ long value = Math.abs(prng.nextLong()) % maximumValue;
+ values.add(value);
+ sensor.record(value);
+ }
+
+ Collections.sort(values);
+
+ int p90Index = (int)Math.ceil(((double)(90 * numberOfValues)) /
100);
+ int p99Index = (int)Math.ceil(((double)(99 * numberOfValues)) /
100);
+
+ double expectedP90 = values.get(p90Index - 1);
+ double expectedP99 = values.get(p99Index - 1);
+
+ assertEquals(expectedP90, (Double) p90.metricValue(), expectedP90
/ 10);
Review comment:
Let's see...
But I am wondering if the condition is right? Should it be:
```
assertTrue("Expected +/- 10% accuracy for exact value of " + expectedP90,
expectedP90 * 0.9 <= (Double) p90.metricValue() && (Double) p90.metricValue()
<= expectedP90 * 1.1);
```
Also possible to split into two asserts of course, but using `assertEquals`
should not work?
----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org
