[JNI] Add readwhilewriting to Java db_bench

Summary: Add readwhilewriting to Java db_bench

Test Plan:
make jni
make jdb_bench

Reviewers: haobo, ankgup87, sdong, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D17619

java/Makefile

@@ -26,9 +26,14 @@ test: java
 db_bench: java
 	javac org/rocksdb/benchmark/*.java
 	rm -rf /tmp/rocksdbjni-bench
-	java -Djava.library.path=.:../ -cp "$(ROCKSDB_JAR):.:./*" org.rocksdb.benchmark.DbBenchmark --threads=1 --benchmarks=fillseq,readrandom
+	java -Djava.library.path=.:../ -cp "$(ROCKSDB_JAR):.:./*" org.rocksdb.benchmark.DbBenchmark --threads=1 --benchmarks=fillseq,readrandom,readwhilewriting
-	java -Djava.library.path=.:../ -cp "$(ROCKSDB_JAR):.:./*" org.rocksdb.benchmark.DbBenchmark --threads=2 --benchmarks=fillseq,readrandom
+	rm -rf /tmp/rocksdbjni-bench
-	java -Djava.library.path=.:../ -cp "$(ROCKSDB_JAR):.:./*" org.rocksdb.benchmark.DbBenchmark --threads=4 --benchmarks=fillseq,readrandom
+	java -Djava.library.path=.:../ -cp "$(ROCKSDB_JAR):.:./*" org.rocksdb.benchmark.DbBenchmark --threads=2 --benchmarks=fillseq,readrandom,readwhilewriting
-	java -Djava.library.path=.:../ -cp "$(ROCKSDB_JAR):.:./*" org.rocksdb.benchmark.DbBenchmark --threads=8 --benchmarks=fillseq,readrandom
+	rm -rf /tmp/rocksdbjni-bench
-	java -Djava.library.path=.:../ -cp "$(ROCKSDB_JAR):.:./*" org.rocksdb.benchmark.DbBenchmark --threads=16 --benchmarks=fillseq,readrandom
+	java -Djava.library.path=.:../ -cp "$(ROCKSDB_JAR):.:./*" org.rocksdb.benchmark.DbBenchmark --threads=4 --benchmarks=fillseq,readrandom,readwhilewriting
-	java -Djava.library.path=.:../ -cp "$(ROCKSDB_JAR):.:./*" org.rocksdb.benchmark.DbBenchmark --threads=32 --benchmarks=fillseq,readrandom
+	rm -rf /tmp/rocksdbjni-bench
+	java -Djava.library.path=.:../ -cp "$(ROCKSDB_JAR):.:./*" org.rocksdb.benchmark.DbBenchmark --threads=8 --benchmarks=fillseq,readrandom,readwhilewriting
+	rm -rf /tmp/rocksdbjni-bench
+	java -Djava.library.path=.:../ -cp "$(ROCKSDB_JAR):.:./*" org.rocksdb.benchmark.DbBenchmark --threads=16 --benchmarks=fillseq,readrandom,readwhilewriting
+	rm -rf /tmp/rocksdbjni-bench
+	java -Djava.library.path=.:../ -cp "$(ROCKSDB_JAR):.:./*" org.rocksdb.benchmark.DbBenchmark --threads=32 --benchmarks=fillseq,readrandom,readwhilewriting

java/org/rocksdb/benchmark/DbBenchmark.java

@@ -47,7 +47,7 @@ class Stats {
   double seconds_;
   long done_;
   long found_;
-  long lastReportDone_;
+  long lastOpTime_;
   long nextReport_;
   long bytes_;
   StringBuilder message_;
@@ -57,10 +57,10 @@ class Stats {
     id_ = id;
     nextReport_ = 100;
     done_ = 0;
-    lastReportDone_ = 0;
     bytes_ = 0;
     seconds_ = 0;
     start_ = System.nanoTime();
+    lastOpTime_ = start_;
     finish_ = start_;
     found_ = 0;
     message_ = new StringBuilder("");
@@ -102,7 +102,7 @@ class Stats {
 
   void finishedSingleOp(int bytes) {
     done_++;
-    lastReportDone_ = System.nanoTime();
+    lastOpTime_ = System.nanoTime();
     bytes_ += bytes;
     if (done_ >= nextReport_) {
       if (nextReport_ < 1000) {
@@ -202,6 +202,16 @@ public class DbBenchmark {
       super(tid, randSeed, numEntries, keyRange);
       writeOpt_ = writeOpt;
       entriesPerBatch_ = entriesPerBatch;
+      maxWritesPerSecond_ = -1;
+    }
+
+    public WriteTask(
+        int tid, long randSeed, long numEntries, long keyRange,
+        WriteOptions writeOpt, long entriesPerBatch, long maxWritesPerSecond) {
+      super(tid, randSeed, numEntries, keyRange);
+      writeOpt_ = writeOpt;
+      entriesPerBatch_ = entriesPerBatch;
+      maxWritesPerSecond_ = maxWritesPerSecond;
     }
 
     @Override public void runTask() throws RocksDBException {
@@ -211,11 +221,16 @@ public class DbBenchmark {
       byte[] key = new byte[keySize_];
       byte[] value = new byte[valueSize_];
 
+      try {
         if (entriesPerBatch_ == 1) {
           for (long i = 0; i < numEntries_; ++i) {
             getKey(key, i, keyRange_);
             db_.put(writeOpt_, key, DbBenchmark.this.gen_.generate(valueSize_));
             stats_.finishedSingleOp(keySize_ + valueSize_);
+            writeRateControl(i);
+            if (isFinished()) {
+              return;
+            }
           }
         } else {
           for (long i = 0; i < numEntries_; i += entriesPerBatch_) {
@@ -227,13 +242,32 @@ public class DbBenchmark {
             }
             db_.write(writeOpt_, batch);
             batch.dispose();
+            writeRateControl(i);
+            if (isFinished()) {
+              return;
             }
           }
         }
+      } catch (InterruptedException e) {
+        // thread has been terminated.
+      }
+    }
+
+    protected void writeRateControl(long writeCount)
+        throws InterruptedException {
+      if (maxWritesPerSecond_ <= 0) return;
+      long minInterval =
+          writeCount * TimeUnit.SECONDS.toNanos(1) / maxWritesPerSecond_;
+      long interval = System.nanoTime() - stats_.start_;
+      if (minInterval - interval > TimeUnit.MILLISECONDS.toNanos(1)) {
+        TimeUnit.NANOSECONDS.sleep(minInterval - interval);
+      }
+    }
 
     abstract protected void getKey(byte[] key, long id, long range);
     protected WriteOptions writeOpt_;
     protected long entriesPerBatch_;
+    protected long maxWritesPerSecond_;
   }
 
   class WriteSequentialTask extends WriteTask {
@@ -243,6 +277,14 @@ public class DbBenchmark {
       super(tid, randSeed, numEntries, keyRange,
             writeOpt, entriesPerBatch);
     }
+    public WriteSequentialTask(
+        int tid, long randSeed, long numEntries, long keyRange,
+        WriteOptions writeOpt, long entriesPerBatch,
+        long maxWritesPerSecond) {
+      super(tid, randSeed, numEntries, keyRange,
+            writeOpt, entriesPerBatch,
+            maxWritesPerSecond);
+    }
     @Override protected void getKey(byte[] key, long id, long range) {
       getFixedKey(key, id);
     }
@@ -255,6 +297,14 @@ public class DbBenchmark {
       super(tid, randSeed, numEntries, keyRange,
             writeOpt, entriesPerBatch);
     }
+    public WriteRandomTask(
+        int tid, long randSeed, long numEntries, long keyRange,
+        WriteOptions writeOpt, long entriesPerBatch,
+        long maxWritesPerSecond) {
+      super(tid, randSeed, numEntries, keyRange,
+            writeOpt, entriesPerBatch,
+            maxWritesPerSecond);
+    }
     @Override protected void getKey(byte[] key, long id, long range) {
       getRandomKey(key, range);
     }
@@ -278,6 +328,9 @@ public class DbBenchmark {
         } else {
           stats_.finishedSingleOp(keySize_);
         }
+        if (isFinished()) {
+          return;
+        }
       }
     }
   }
@@ -312,7 +365,9 @@ public class DbBenchmark {
     useExisting_ = (boolean) flags.get(Flag.use_existing_db);
     randSeed_ = (long) flags.get(Flag.seed);
     databaseDir_ = (String) flags.get(Flag.db);
+    writesPerSeconds_ = (int) flags.get(Flag.writes_per_second);
     gen_ = new RandomGenerator(compressionRatio_);
+    finishLock_ = new Object();
   }
 
   private void run() throws RocksDBException {
@@ -325,29 +380,25 @@ public class DbBenchmark {
 
     for (String benchmark : benchmarks_) {
       List<Callable<Stats>> tasks = new ArrayList<Callable<Stats>>();
+      List<Callable<Stats>> bgTasks = new ArrayList<Callable<Stats>>();
       WriteOptions writeOpt = new WriteOptions();
       int currentTaskId = 0;
-      int concurrentThreads = threadNum_;
       boolean known = true;
 
       if (benchmark.equals("fillseq")) {
         tasks.add(new WriteSequentialTask(
-            currentTaskId, randSeed_, num_, num_, writeOpt, 1));
+            currentTaskId++, randSeed_, num_, num_, writeOpt, 1));
-        concurrentThreads = 1;
       } else if (benchmark.equals("fillbatch")) {
         tasks.add(new WriteRandomTask(
-            currentTaskId, randSeed_, num_ / 1000, num_, writeOpt, 1000));
+            currentTaskId++, randSeed_, num_ / 1000, num_, writeOpt, 1000));
-        concurrentThreads = 1;
       } else if (benchmark.equals("fillrandom")) {
         tasks.add(new WriteRandomTask(
-            currentTaskId, randSeed_, num_, num_, writeOpt, 1));
+            currentTaskId++, randSeed_, num_, num_, writeOpt, 1));
-        concurrentThreads = 1;
       } else if (benchmark.equals("fillsync")) {
         writeOpt.setSync(true);
         tasks.add(new WriteRandomTask(
-            currentTaskId, randSeed_, num_ / 1000, num_ / 1000,
+            currentTaskId++, randSeed_, num_ / 1000, num_ / 1000,
             writeOpt, 1));
-        concurrentThreads = 1;
       } else if (benchmark.equals("readseq")) {
         for (int t = 0; t < threadNum_; ++t) {
           tasks.add(new ReadSequentialTask(
@@ -359,6 +410,15 @@ public class DbBenchmark {
           tasks.add(new ReadRandomTask(
               currentTaskId++, randSeed_, reads_ / threadNum_, num_));
         }
+      } else if (benchmark.equals("readwhilewriting")) {
+        WriteTask writeTask = new WriteRandomTask(
+            -1, randSeed_, Long.MAX_VALUE, num_, writeOpt, 1, writesPerSeconds_);
+        writeTask.stats_.setExcludeFromMerge();
+        bgTasks.add(writeTask);
+        for (int t = 0; t < threadNum_; ++t) {
+          tasks.add(new ReadRandomTask(
+              currentTaskId++, randSeed_, reads_ / threadNum_, num_));
+        }
       } else if (benchmark.equals("readhot")) {
         for (int t = 0; t < threadNum_; ++t) {
           tasks.add(new ReadRandomTask(
@@ -373,17 +433,34 @@ public class DbBenchmark {
       }
       if (known) {
         ExecutorService executor = Executors.newCachedThreadPool();
+        ExecutorService bgExecutor = Executors.newCachedThreadPool();
         try {
+          // measure only the main executor time
+          List<Future<Stats>> bgResults = new ArrayList<Future<Stats>>();
+          for (Callable bgTask : bgTasks) {
+            bgResults.add(bgExecutor.submit(bgTask));
+          }
           start();
           List<Future<Stats>> results = executor.invokeAll(tasks);
           executor.shutdown();
-          boolean finished = executor.awaitTermination(3, TimeUnit.DAYS);
+          boolean finished = executor.awaitTermination(10, TimeUnit.SECONDS);
-          // do something
-          stop(benchmark, results, concurrentThreads);
           if (!finished) {
-            // do something else
+            System.out.format(
-            System.out.format("Benchmark %s was not finished before timeout.");
+                "Benchmark %s was not finished before timeout.",
+                benchmark);
+            executor.shutdownNow();
           }
+          setFinished(true);
+          bgExecutor.shutdown();
+          finished = bgExecutor.awaitTermination(10, TimeUnit.SECONDS);
+          if (!finished) {
+            System.out.format(
+                "Benchmark %s was not finished before timeout.",
+                benchmark);
+            bgExecutor.shutdownNow();
+          }
+
+          stop(benchmark, results, currentTaskId);
         } catch (InterruptedException e) {
           System.err.println(e);
         }
@@ -423,6 +500,7 @@ public class DbBenchmark {
   }
 
   private void start() {
+    setFinished(false);
     startTime_ = System.nanoTime();
   }
 
@@ -449,7 +527,7 @@ public class DbBenchmark {
     }
 
     System.out.printf(
-        "%-12s : %11.5f micros/op; %6.1f MB/s; %d / %d task(s) finished.\n",
+        "%-16s : %11.5f micros/op; %6.1f MB/s; %d / %d task(s) finished.\n",
         benchmark, elapsedSeconds * 1e6 / num_,
         (stats.bytes_ / 1048576.0) / elapsedSeconds,
         taskFinishedCount, concurrentThreads);
@@ -536,15 +614,18 @@ public class DbBenchmark {
             "fillrandom"),
         "Comma-separated list of operations to run in the specified order\n" +
         "\tActual benchmarks:\n" +
-        "\t\tfillseq    -- write N values in sequential key order in async mode\n" +
+        "\t\tfillseq          -- write N values in sequential key order in async mode.\n" +
-        "\t\tfillrandom -- write N values in random key order in async mode\n" +
+        "\t\tfillrandom       -- write N values in random key order in async mode.\n" +
         "\t\tfillbatch        -- write N/1000 batch where each batch has 1000 values\n" +
-        "\t\t              in random key order in sync mode\n" +
+        "\t\t                    in random key order in sync mode.\n" +
-        "\t\tfillsync   -- write N/100 values in random key order in sync mode\n" +
+        "\t\tfillsync         -- write N/100 values in random key order in sync mode.\n" +
-        "\t\tfill100K   -- write N/1000 100K values in random order in async mode\n" +
+        "\t\tfill100K         -- write N/1000 100K values in random order in async mode.\n" +
-        "\t\treadseq    -- read N times sequentially\n" +
+        "\t\treadseq          -- read N times sequentially.\n" +
-        "\t\treadrandom -- read N times in random order\n" +
+        "\t\treadrandom       -- read N times in random order.\n" +
-        "\t\treadhot    -- read N times in random order from 1% section of DB\n" +
+        "\t\treadhot          -- read N times in random order from 1% section of DB.\n" +
+        "\t\treadwhilewriting -- measure the read performance of multiple readers\n" +
+        "\t\t                    with a bg single writer.  The write rate of the bg\n" +
+        "\t\t                    is capped by --writes_per_second.\n" +
         "\tMeta Operations:\n" +
         "\t\tdelete            -- delete DB") {
       @Override public Object parseValue(String value) {
@@ -613,6 +694,15 @@ public class DbBenchmark {
       }
     },
 
+    writes_per_second(10000,
+        "The write-rate of the background writer used in the\n" +
+        "`readwhilewriting` benchmark.  Non-positive number indicates\n" +
+        "using an unbounded write-rate in `readwhilewriting` benchmark.") {
+      @Override public Object parseValue(String value) {
+        return Integer.parseInt(value);
+      }
+    },
+
     cache_size(-1,
         "Number of bytes to use as a cache of uncompressed data.\n" +
         "\tNegative means use default settings.") {
@@ -682,6 +772,18 @@ public class DbBenchmark {
     }
   }
 
+  boolean isFinished() {
+    synchronized(finishLock_) {
+      return isFinished_;
+    }
+  }
+
+  void setFinished(boolean flag) {
+    synchronized(finishLock_) {
+      isFinished_ = flag;
+    }
+  }
+
   RocksDB db_;
   final List<String> benchmarks_;
   final int num_;
@@ -690,10 +792,13 @@ public class DbBenchmark {
   final int valueSize_;
   final int writeBufferSize_;
   final int threadNum_;
+  final int writesPerSeconds_;
   final long randSeed_;
   final boolean useExisting_;
   final String databaseDir_;
   final double compressionRatio_;
   RandomGenerator gen_;
   long startTime_;
+  Object finishLock_;
+  boolean isFinished_;
 }