Expose max_background_jobs option in RocksJava

Summary:
This option was introduced in the C++ API in RocksDB 5.6 in bb01c1880c0c89a6cf338e22fd54e7e25b7d12ba . Now, exposing it through RocksJava API.
Closes https://github.com/facebook/rocksdb/pull/2908

Differential Revision: D5864224

Pulled By: sagar0

fbshipit-source-id: 140aa55dcf74b14e4d11219d996735c7fdddf513

java/benchmark/src/main/java/org/rocksdb/benchmark/DbBenchmark.java

@@ -543,6 +543,7 @@ public class DbBenchmark {
         (Integer)flags_.get(Flag.max_background_compactions));
     options.setMaxBackgroundFlushes(
         (Integer)flags_.get(Flag.max_background_flushes));
+    options.setMaxBackgroundJobs((Integer) flags_.get(Flag.max_background_jobs));
     options.setMaxOpenFiles(
         (Integer)flags_.get(Flag.open_files));
     options.setUseFsync(
@@ -1116,6 +1117,14 @@ public class DbBenchmark {
         return Integer.parseInt(value);
       }
     },
+    max_background_jobs(defaultOptions_.maxBackgroundJobs(),
+        "The maximum number of concurrent background jobs\n"
+            + "\tthat can occur in parallel.") {
+      @Override
+      public Object parseValue(String value) {
+        return Integer.parseInt(value);
+      }
+    },
     /* TODO(yhchiang): enable the following
     compaction_style((int32_t) defaultOptions_.compactionStyle(),
         "style of compaction: level-based vs universal.") {

java/rocksjni/options.cc

@@ -668,6 +668,28 @@ void Java_org_rocksdb_Options_setMaxBackgroundFlushes(
       static_cast<int>(max_background_flushes);
 }
 
+/*
+ * Class:     org_rocksdb_Options
+ * Method:    maxBackgroundJobs
+ * Signature: (J)I
+ */
+jint Java_org_rocksdb_Options_maxBackgroundJobs(JNIEnv* env, jobject jobj,
+                                                jlong jhandle) {
+  return reinterpret_cast<rocksdb::Options*>(jhandle)->max_background_jobs;
+}
+
+/*
+ * Class:     org_rocksdb_Options
+ * Method:    setMaxBackgroundJobs
+ * Signature: (JI)V
+ */
+void Java_org_rocksdb_Options_setMaxBackgroundJobs(JNIEnv* env, jobject jobj,
+                                                   jlong jhandle,
+                                                   jint max_background_jobs) {
+  reinterpret_cast<rocksdb::Options*>(jhandle)->max_background_jobs =
+      static_cast<int>(max_background_jobs);
+}
+
 /*
  * Class:     org_rocksdb_Options
  * Method:    maxLogFileSize
@@ -4700,6 +4722,28 @@ jint Java_org_rocksdb_DBOptions_maxBackgroundFlushes(
       max_background_flushes;
 }
 
+/*
+ * Class:     org_rocksdb_DBOptions
+ * Method:    setMaxBackgroundJobs
+ * Signature: (JI)V
+ */
+void Java_org_rocksdb_DBOptions_setMaxBackgroundJobs(JNIEnv* env, jobject jobj,
+                                                     jlong jhandle,
+                                                     jint max_background_jobs) {
+  reinterpret_cast<rocksdb::DBOptions*>(jhandle)->max_background_jobs =
+      static_cast<int>(max_background_jobs);
+}
+
+/*
+ * Class:     org_rocksdb_DBOptions
+ * Method:    maxBackgroundJobs
+ * Signature: (J)I
+ */
+jint Java_org_rocksdb_DBOptions_maxBackgroundJobs(JNIEnv* env, jobject jobj,
+                                                  jlong jhandle) {
+  return reinterpret_cast<rocksdb::DBOptions*>(jhandle)->max_background_jobs;
+}
+
 /*
  * Class:     org_rocksdb_DBOptions
  * Method:    setMaxLogFileSize

java/src/main/java/org/rocksdb/DBOptions.java

@@ -390,8 +390,20 @@ public class DBOptions
   }
 
   @Override
-  public DBOptions setMaxLogFileSize(
-      final long maxLogFileSize) {
+  public DBOptions setMaxBackgroundJobs(final int maxBackgroundJobs) {
+    assert(isOwningHandle());
+    setMaxBackgroundJobs(nativeHandle_, maxBackgroundJobs);
+    return this;
+  }
+
+  @Override
+  public int maxBackgroundJobs() {
+    assert(isOwningHandle());
+    return maxBackgroundJobs(nativeHandle_);
+  }
+
+  @Override
+  public DBOptions setMaxLogFileSize(final long maxLogFileSize) {
     assert(isOwningHandle());
     setMaxLogFileSize(nativeHandle_, maxLogFileSize);
     return this;
@@ -998,6 +1010,8 @@ public class DBOptions
   private native void setMaxBackgroundFlushes(
       long handle, int maxBackgroundFlushes);
   private native int maxBackgroundFlushes(long handle);
+  private native void setMaxBackgroundJobs(long handle, int maxBackgroundJobs);
+  private native int maxBackgroundJobs(long handle);
   private native void setMaxLogFileSize(long handle, long maxLogFileSize)
       throws IllegalArgumentException;
   private native long maxLogFileSize(long handle);

java/src/main/java/org/rocksdb/DBOptionsInterface.java

@@ -446,6 +446,8 @@ public interface DBOptionsInterface<T extends DBOptionsInterface> {
    *
    * @param baseBackgroundCompactions Suggested number of background compaction
    *     jobs
+   *
+   * @deprecated Use {@link #setMaxBackgroundJobs(int)}
    */
   void setBaseBackgroundCompactions(int baseBackgroundCompactions);
 
@@ -485,6 +487,8 @@ public interface DBOptionsInterface<T extends DBOptionsInterface> {
    * @return the maximum number of concurrent background compaction jobs.
    * @see RocksEnv#setBackgroundThreads(int)
    * @see RocksEnv#setBackgroundThreads(int, int)
+   *
+   * @deprecated Use {@link #setMaxBackgroundJobs(int)}
    */
   int maxBackgroundCompactions();
 
@@ -522,6 +526,8 @@ public interface DBOptionsInterface<T extends DBOptionsInterface> {
    * @see RocksEnv#setBackgroundThreads(int)
    * @see RocksEnv#setBackgroundThreads(int, int)
    * @see #maxBackgroundCompactions()
+   *
+   * @deprecated Use {@link #setMaxBackgroundJobs(int)}
    */
   T setMaxBackgroundFlushes(int maxBackgroundFlushes);
 
@@ -537,6 +543,25 @@ public interface DBOptionsInterface<T extends DBOptionsInterface> {
    */
   int maxBackgroundFlushes();
 
+  /**
+   * Specifies the maximum number of concurrent background jobs (both flushes
+   * and compactions combined).
+   * Default: 2
+   *
+   * @param maxBackgroundJobs number of max concurrent background jobs
+   * @return the instance of the current object.
+   */
+  T setMaxBackgroundJobs(int maxBackgroundJobs);
+
+  /**
+   * Returns the maximum number of concurrent background jobs (both flushes
+   * and compactions combined).
+   * Default: 2
+   *
+   * @return the maximum number of concurrent background jobs.
+   */
+  int maxBackgroundJobs();
+
   /**
    * Specifies the maximum size of a info log file. If the current log file
    * is larger than `max_log_file_size`, a new info log file will

java/src/main/java/org/rocksdb/Options.java

@@ -443,6 +443,19 @@ public class Options extends RocksObject
     return this;
   }
 
+  @Override
+  public int maxBackgroundJobs() {
+    assert(isOwningHandle());
+    return maxBackgroundJobs(nativeHandle_);
+  }
+
+  @Override
+  public Options setMaxBackgroundJobs(final int maxBackgroundJobs) {
+    assert(isOwningHandle());
+    setMaxBackgroundJobs(nativeHandle_, maxBackgroundJobs);
+    return this;
+  }
+
   @Override
   public long maxLogFileSize() {
     assert(isOwningHandle());
@@ -1591,6 +1604,8 @@ public class Options extends RocksObject
   private native void setMaxBackgroundFlushes(
       long handle, int maxBackgroundFlushes);
   private native int maxBackgroundFlushes(long handle);
+  private native void setMaxBackgroundJobs(long handle, int maxMaxBackgroundJobs);
+  private native int maxBackgroundJobs(long handle);
   private native void setMaxLogFileSize(long handle, long maxLogFileSize)
       throws IllegalArgumentException;
   private native long maxLogFileSize(long handle);

java/src/test/java/org/rocksdb/DBOptionsTest.java

@@ -240,6 +240,15 @@ public class DBOptionsTest {
     }
   }
 
+  @Test
+  public void maxBackgroundJobs() {
+    try (final DBOptions opt = new DBOptions()) {
+      final int intValue = rand.nextInt();
+      opt.setMaxBackgroundJobs(intValue);
+      assertThat(opt.maxBackgroundJobs()).isEqualTo(intValue);
+    }
+  }
+
   @Test
   public void maxLogFileSize() throws RocksDBException {
     try(final DBOptions opt = new DBOptions()) {

java/src/test/java/org/rocksdb/OptionsTest.java

@@ -458,6 +458,15 @@ public class OptionsTest {
     }
   }
 
+  @Test
+  public void maxBackgroundJobs() {
+    try (final Options opt = new Options()) {
+      final int intValue = rand.nextInt();
+      opt.setMaxBackgroundJobs(intValue);
+      assertThat(opt.maxBackgroundJobs()).isEqualTo(intValue);
+    }
+  }
+
   @Test
   public void maxLogFileSize() throws RocksDBException {
     try (final Options opt = new Options()) {