Merge pull request #125 from keith-turner/gcpt

Add group commit performance test

src/main/java/org/apache/accumulo/testing/performance/tests/GroupCommitPT.java

@@ -0,0 +1,233 @@
+/*
+ * 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.accumulo.testing.performance.tests;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Random;
+import java.util.SortedSet;
+import java.util.TreeSet;
+
+import org.apache.accumulo.core.client.BatchWriter;
+import org.apache.accumulo.core.client.BatchWriterConfig;
+import org.apache.accumulo.core.client.MutationsRejectedException;
+import org.apache.accumulo.core.client.Scanner;
+import org.apache.accumulo.core.client.admin.NewTableConfiguration;
+import org.apache.accumulo.core.conf.Property;
+import org.apache.accumulo.core.data.Key;
+import org.apache.accumulo.core.data.Mutation;
+import org.apache.accumulo.core.data.Value;
+import org.apache.accumulo.core.security.Authorizations;
+import org.apache.accumulo.testing.performance.Environment;
+import org.apache.accumulo.testing.performance.PerformanceTest;
+import org.apache.accumulo.testing.performance.Report;
+import org.apache.accumulo.testing.performance.SystemConfiguration;
+import org.apache.hadoop.io.Text;
+
+import com.google.common.base.Preconditions;
+
+public class GroupCommitPT implements PerformanceTest {
+
+  private static final int NUM_MUTATIONS = 2048 * 1024;
+  private static final int NUM_FLUSHES = 1024;
+
+  static Mutation createRandomMutation(Random rand) {
+    byte row[] = new byte[16];
+
+    rand.nextBytes(row);
+
+    Mutation m = new Mutation(row);
+
+    byte cq[] = new byte[8];
+    byte val[] = new byte[16];
+
+    for (int i = 0; i < 3; i++) {
+      rand.nextBytes(cq);
+      rand.nextBytes(val);
+      m.put("cf".getBytes(), cq, val);
+    }
+
+    return m;
+  }
+
+  static class WriteTask implements Runnable {
+
+    private int batchSize;
+    private BatchWriter bw;
+    private volatile int written = 0;
+
+    WriteTask(BatchWriter bw, int numMutations) throws Exception {
+      Preconditions.checkArgument(numMutations >= NUM_FLUSHES);
+      Preconditions.checkArgument(numMutations % NUM_FLUSHES == 0);
+      this.bw = bw;
+      this.batchSize = numMutations / NUM_FLUSHES;
+    }
+
+    @Override
+    public void run() {
+      Random rand = new Random();
+
+      int written = 0;
+
+      try {
+        for (int i = 0; i < NUM_FLUSHES; i++) {
+          Mutation mut = createRandomMutation(rand);
+
+          for (int j = 0; j < batchSize; j++) {
+            bw.addMutation(mut);
+            written++;
+          }
+
+          bw.flush();
+        }
+      } catch (Exception e) {
+        e.printStackTrace();
+      } finally {
+        try {
+          bw.close();
+        } catch (MutationsRejectedException e) {
+          e.printStackTrace();
+        }
+
+      }
+
+      this.written = written;
+    }
+
+    public int getWritten() {
+      return written;
+    }
+  }
+
+  @Override
+  public SystemConfiguration getSystemConfig() {
+
+    Map<String,String> siteCfg = new HashMap<>();
+
+    siteCfg.put(Property.TSERV_MINTHREADS.getKey(), "128");
+    siteCfg.put(Property.TABLE_DURABILITY.getKey(), "sync");
+
+    return new SystemConfiguration().setAccumuloConfig(siteCfg);
+  }
+
+  @Override
+  public Report runTest(Environment env) throws Exception {
+
+    Report.Builder report = Report.builder();
+    report.id("mutslam");
+    report.description("Data written to Accumulo is appended to a write ahead log before its made "
+        + "available for scan.  There is a single write ahead log per tablet server.  Data from "
+        + "multiple concurrent clients is batched together and appended to the write ahead log, "
+        + "this is called group commit.  If group commit is not working properly, then performance"
+        + " of concurrent writes could suffer.  This performance test measures group commit.  In "
+        + "an Accumulo client, when the batch writer is flushed this forces an append to the write"
+        + " ahead log.  The batch writer flush call does not return until the append is complete. "
+        + "This test writes the same amount of data using different numbers of threads to check if"
+        + " group commit is working properly.  When the test is using one thread it will write "
+        + "2048K total mutations calling flush on the batchwriter 1024 times.  When"
+        + " the test is running two threads, each thread will write 1024K mutations calling "
+        + "flush 1024 times.  The pattern is that as the number of threads increases"
+        + ", the amount of data written per thread decreases proportionally.  However the number of"
+        + " flushes done by threads is constant.  If group commit is working well, then the overall"
+        + " write rate should not be significantly less as the number of threads increases.");
+
+    report.parameter("num_mutations", NUM_MUTATIONS,
+        "The total number of mutations each test will write.  Each thread in a test will write num_mutations/num_threads_in_test mutations.");
+    report.parameter("num_flushes", NUM_FLUSHES,
+        "The number of times each thread will flush its batch writer.  The flushes are spread evenly between mutations.");
+
+    // number of threads to run for each test
+    int tests[] = new int[] {1, 2, 4, 8, 16, 32, 64};
+
+    // run warm up test
+    for (int numThreads : tests) {
+      runTest(report, env, numThreads, true);
+    }
+
+    // run real test
+    for (int numThreads : tests) {
+      runTest(report, env, numThreads, false);
+    }
+
+    return report.build();
+  }
+
+  private void runTest(Report.Builder report, Environment env, int numThreads, boolean warmup)
+      throws Exception {
+
+    Preconditions.checkArgument(NUM_MUTATIONS % numThreads == 0);
+
+    // presplit tablet to allow more concurrency to tablet in memory map updates, so this does not
+    // impeded write ahead log appends.
+    NewTableConfiguration ntc = new NewTableConfiguration();
+    SortedSet<Text> splits = new TreeSet<>();
+    for (int s = 16; s < 256; s += 16) {
+      splits.add(new Text(new byte[] {(byte) s}));
+    }
+    ntc.withSplits(splits);
+
+    String tableName = "mutslam";
+    env.getClient().tableOperations().create(tableName, ntc);
+
+    // scan just to wait for tablet be online
+    Scanner scanner = env.getClient().createScanner(tableName, Authorizations.EMPTY);
+    for (Map.Entry<Key,Value> entry : scanner) {
+      entry.getValue();
+    }
+
+    int mutationsPerThread = NUM_MUTATIONS / numThreads;
+
+    ArrayList<WriteTask> wasks = new ArrayList<WriteTask>();
+    ArrayList<Thread> threads = new ArrayList<Thread>();
+
+    for (int i = 0; i < numThreads; i++) {
+      WriteTask wask = new WriteTask(env.getClient().createBatchWriter(tableName,
+          new BatchWriterConfig().setMaxWriteThreads(1)), mutationsPerThread);
+
+      wasks.add(wask);
+      Thread thread = new Thread(wask);
+      threads.add(thread);
+    }
+
+    long t1 = System.currentTimeMillis();
+
+    for (Thread thread : threads) {
+      thread.start();
+    }
+
+    for (Thread thread : threads) {
+      thread.join();
+    }
+
+    long t2 = System.currentTimeMillis();
+
+    // ensure all thread wrote the expected number of mutations
+    Preconditions.checkState(wasks.stream().mapToInt(WriteTask::getWritten).sum() == NUM_MUTATIONS);
+
+    env.getClient().tableOperations().delete(tableName);
+    if (warmup) {
+      report.info("warmup_rate_" + numThreads, NUM_MUTATIONS, t2 - t1, "The warmup rate at which "
+          + numThreads + " threads wrote data. The rate is mutations per second.");
+    } else {
+      report.result("rate_" + numThreads, NUM_MUTATIONS, t2 - t1, "The rate at which " + numThreads
+          + " threads wrote data. The rate is mutations per second.");
+    }
+  }
+
+}