diff --git src/test/java/org/apache/hadoop/hbase/metrics/TestMetricsHistogram.java src/test/java/org/apache/hadoop/hbase/metrics/TestMetricsHistogram.java index da0e87e..0d853fa 100644 --- src/test/java/org/apache/hadoop/hbase/metrics/TestMetricsHistogram.java +++ src/test/java/org/apache/hadoop/hbase/metrics/TestMetricsHistogram.java @@ -14,20 +14,27 @@ * 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.hadoop.hbase.metrics; -import java.util.Arrays; +import static org.mockito.Matchers.anyFloat; +import static org.mockito.Matchers.anyLong; +import static org.mockito.Matchers.eq; +import static org.mockito.Mockito.mock; +import static org.mockito.Mockito.verify; + import java.util.Random; -import org.apache.hadoop.hbase.metrics.histogram.MetricsHistogram; import org.apache.hadoop.hbase.SmallTests; -import com.yammer.metrics.stats.Snapshot; +import org.apache.hadoop.hbase.metrics.histogram.MetricsHistogram; +import org.apache.hadoop.metrics.MetricsRecord; import org.junit.Assert; import org.junit.Test; import org.junit.experimental.categories.Category; +import com.yammer.metrics.stats.Snapshot; + +@SuppressWarnings("deprecation") @Category(SmallTests.class) public class TestMetricsHistogram { @@ -42,60 +49,64 @@ public class TestMetricsHistogram { Assert.assertEquals(100, h.getCount()); Assert.assertEquals(0, h.getMin()); Assert.assertEquals(99, h.getMax()); + Assert.assertEquals(49.5d, h.getMean(), 0.01); } - private static int safeIndex(int i, int len) { - if (i < len && i>= 0) { - return i; - } else if (i >= len) { - return len - 1; - } else { - return 0; - } - } - @Test - public void testRandom() { - final Random r = new Random(); + public void testSnapshotPercentiles() { final MetricsHistogram h = new MetricsHistogram("testHistogram", null); - - final long[] data = new long[1000]; - - for (int i = 0; i < data.length; i++) { - data[i] = (long) (r.nextGaussian() * 10000.0); - h.update(data[i]); - } + final long[] data = genRandomData(h); final Snapshot s = h.getSnapshot(); - Arrays.sort(data); - - // as long as the histogram chooses an item with index N+/-slop, accept it - final int slop = 20; - // make sure the median, 75th percentile and 95th percentile are good - final int medianIndex = data.length / 2; - final long minAcceptableMedian = data[safeIndex(medianIndex - slop, - data.length)]; - final long maxAcceptableMedian = data[safeIndex(medianIndex + slop, - data.length)]; - Assert.assertTrue(s.getMedian() >= minAcceptableMedian - && s.getMedian() <= maxAcceptableMedian); + assertPercentile(data, 50, s.getMedian()); + assertPercentile(data, 75, s.get75thPercentile()); + assertPercentile(data, 95, s.get95thPercentile()); + assertPercentile(data, 98, s.get98thPercentile()); + assertPercentile(data, 99, s.get99thPercentile()); + assertPercentile(data, 99.9, s.get999thPercentile()); + } - final int seventyFifthIndex = (int) (data.length * 0.75); - final long minAcceptableseventyFifth = data[safeIndex(seventyFifthIndex - - slop, data.length)]; - final long maxAcceptableseventyFifth = data[safeIndex(seventyFifthIndex - + slop, data.length)]; - Assert.assertTrue(s.get75thPercentile() >= minAcceptableseventyFifth - && s.get75thPercentile() <= maxAcceptableseventyFifth); + @Test + public void testPushMetric() { + final MetricsHistogram h = new MetricsHistogram("testHistogram", null); + genRandomData(h); + + MetricsRecord mr = mock(MetricsRecord.class); + h.pushMetric(mr); + + verify(mr).setMetric("testHistogram_num_ops", 10000L); + verify(mr).setMetric(eq("testHistogram_min"), anyLong()); + verify(mr).setMetric(eq("testHistogram_max"), anyLong()); + verify(mr).setMetric(eq("testHistogram_mean"), anyFloat()); + verify(mr).setMetric(eq("testHistogram_std_dev"), anyFloat()); + verify(mr).setMetric(eq("testHistogram_median"), anyFloat()); + verify(mr).setMetric(eq("testHistogram_75th_percentile"), anyFloat()); + verify(mr).setMetric(eq("testHistogram_95th_percentile"), anyFloat()); + verify(mr).setMetric(eq("testHistogram_99th_percentile"), anyFloat()); + } - final int ninetyFifthIndex = (int) (data.length * 0.95); - final long minAcceptableninetyFifth = data[safeIndex(ninetyFifthIndex - - slop, data.length)]; - final long maxAcceptableninetyFifth = data[safeIndex(ninetyFifthIndex - + slop, data.length)]; - Assert.assertTrue(s.get95thPercentile() >= minAcceptableninetyFifth - && s.get95thPercentile() <= maxAcceptableninetyFifth); + private void assertPercentile(long[] data, double percentile, double value) { + int count = 0; + for (long v : data) { + if (v < value) { + count++; + } + } + Assert.assertEquals("Wrong " + percentile + " percentile", + (int)(percentile / 100), count / data.length); + } + + private long[] genRandomData(final MetricsHistogram h) { + final Random r = new Random(); + final long[] data = new long[10000]; + for (int i = 0; i < data.length; i++) { + data[i] = (long) (r.nextGaussian() * 10000); + h.update(data[i]); + } + + return data; } + }