ryucc commented on code in PR #26437:
URL: https://github.com/apache/beam/pull/26437#discussion_r1179501152


##########
runners/samza/src/main/java/org/apache/beam/runners/samza/runtime/SamzaInputMetricOp.java:
##########
@@ -0,0 +1,89 @@
+/*
+ * 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.beam.runners.samza.runtime;
+
+import java.math.BigInteger;
+import java.util.concurrent.atomic.AtomicLong;
+import java.util.concurrent.atomic.AtomicReference;
+import org.apache.beam.runners.samza.metrics.BeamTransformMetricRegistry;
+import org.apache.beam.sdk.util.WindowedValue;
+import org.joda.time.Instant;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * SamzaInputMetricOp is a {@link SamzaMetricOp} that emits & maintains 
default transform metrics
+ * for input PCollection to the transform. It emits the input throughput and 
maintains avg arrival
+ * time for input PCollection per watermark.
+ *
+ * <p>Assumes that {@code SamzaInputMetricOp#processWatermark(Instant, 
OpEmitter)} is exclusive of
+ * {@code SamzaInputMetricOp#processElement(Instant, OpEmitter)}. 
Specifically, the processWatermark
+ * method assumes that no calls to processElement will be made during its 
execution, and vice versa.
+ *
+ * @param <T> The type of the elements in the input PCollection.
+ */
+public class SamzaInputMetricOp<T> extends SamzaMetricOp<T> {
+  private static final Logger LOG = 
LoggerFactory.getLogger(SamzaInputMetricOp.class);
+  // Counters to maintain avg arrival time per watermark for input PCollection.
+  private AtomicLong count;
+  private AtomicReference<BigInteger> sumOfTimestamps;
+
+  public SamzaInputMetricOp(
+      String pValue,
+      String transformFullName,
+      BeamTransformMetricRegistry beamTransformMetricRegistry) {
+    super(pValue, transformFullName, beamTransformMetricRegistry);
+    this.count = new AtomicLong(0L);
+    this.sumOfTimestamps = new AtomicReference<>(BigInteger.ZERO);
+  }
+
+  @Override
+  public void processElement(WindowedValue<T> inputElement, OpEmitter<T> 
emitter) {
+    count.incrementAndGet();
+    sumOfTimestamps.updateAndGet(sum -> 
sum.add(BigInteger.valueOf(System.nanoTime())));
+    beamTransformMetricRegistry
+        .getTransformMetrics()
+        .getTransformInputThroughput(transformFullName)
+        .inc();
+    emitter.emitElement(inputElement);
+  }
+
+  @Override
+  public void processWatermark(Instant watermark, OpEmitter<T> emitter) {
+    if (LOG.isDebugEnabled()) {

Review Comment:
   I thought we only need the `if (LOG.isDebugEnabled()) {` check when the 
construction of the log message is expensive. Else, we can just write 
`LOG.debug(...)`, and let log4j filter out the message.



-- 
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.

To unsubscribe, e-mail: [email protected]

For queries about this service, please contact Infrastructure at:
[email protected]

Reply via email to