[RocksJava] Fix test failure of compactRangeToLevel

Summary:
Rewrite Java tests compactRangeToLevel and compactRangeToLevelColumnFamily
to make them more deterministic and robust.

Test Plan:
make rocksdbjava
make jtest

Reviewers: anthony, fyrz, adamretter, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D40941

java/src/test/java/org/rocksdb/RocksDBTest.java

@@ -601,48 +601,73 @@ public class RocksDBTest {
     RocksDB db = null;
     Options opt = null;
     try {
+      final int NUM_KEYS_PER_L0_FILE = 100;
+      final int KEY_SIZE = 20;
+      final int VALUE_SIZE = 300;
+      final int L0_FILE_SIZE =
+          NUM_KEYS_PER_L0_FILE * (KEY_SIZE + VALUE_SIZE);
+      final int NUM_L0_FILES = 10;
+      final int TEST_SCALE = 5;
+      final int KEY_INTERVAL = 100;
       opt = new Options().
           setCreateIfMissing(true).
           setCompactionStyle(CompactionStyle.LEVEL).
-          setNumLevels(4).
-          setWriteBufferSize(100<<10).
-          setLevelZeroFileNumCompactionTrigger(3).
-          setTargetFileSizeBase(200 << 10).
-          setTargetFileSizeMultiplier(1).
-          setMaxBytesForLevelBase(500 << 10).
-          setMaxBytesForLevelMultiplier(1).
-          setDisableAutoCompactions(false);
-      // open database
-      db = RocksDB.open(opt,
-          dbFolder.getRoot().getAbsolutePath());
-      // fill database with key/value pairs
-      byte[] b = new byte[10000];
-      for (int i = 0; i < 200; i++) {
-        rand.nextBytes(b);
-        db.put((String.valueOf(i)).getBytes(), b);
-      }
-      db.flush(new FlushOptions().setWaitForFlush(true));
-      db.close();
-      opt.setTargetFileSizeBase(Long.MAX_VALUE).
+          setNumLevels(5).
+          // a slightly bigger write buffer than L0 file
+          // so that we can ensure manual flush always
+          // go before background flush happens.
+          setWriteBufferSize(L0_FILE_SIZE * 2).
+          // Disable auto L0 -> L1 compaction
+          setLevelZeroFileNumCompactionTrigger(20).
+          setTargetFileSizeBase(L0_FILE_SIZE * 100).
           setTargetFileSizeMultiplier(1).
-          setMaxBytesForLevelBase(Long.MAX_VALUE).
-          setMaxBytesForLevelMultiplier(1).
+          // To disable auto compaction
+          setMaxBytesForLevelBase(NUM_L0_FILES * L0_FILE_SIZE * 100).
+          setMaxBytesForLevelMultiplier(2).
           setDisableAutoCompactions(true);
-
       db = RocksDB.open(opt,
           dbFolder.getRoot().getAbsolutePath());
+      // fill database with key/value pairs
+      byte[] value = new byte[VALUE_SIZE];
+      int int_key = 0;
+      for (int round = 0; round < 5; ++round) {
+        int initial_key = int_key;
+        for (int f = 1; f <= NUM_L0_FILES; ++f) {
+          for (int i = 0; i < NUM_KEYS_PER_L0_FILE; ++i) {
+            int_key += KEY_INTERVAL;
+            rand.nextBytes(value);
 
-      db.compactRange(true, 0, 0);
-      for (int i = 0; i < 4; i++) {
-        if (i == 0) {
-          assertThat(
-              db.getProperty("rocksdb.num-files-at-level" + i)).
-              isEqualTo("1");
-        } else {
+            db.put(String.format("%020d", int_key).getBytes(),
+                   value);
+          }
+          db.flush(new FlushOptions().setWaitForFlush(true));
+          // Make sure we do create one more L0 files.
           assertThat(
-              db.getProperty("rocksdb.num-files-at-level" + i)).
-              isEqualTo("0");
+              db.getProperty("rocksdb.num-files-at-level0")).
+              isEqualTo("" + f);
         }
+
+        // Compact all L0 files we just created
+        db.compactRange(
+            String.format("%020d", initial_key).getBytes(),
+            String.format("%020d", int_key - 1).getBytes());
+        // Making sure there isn't any L0 files.
+        assertThat(
+            db.getProperty("rocksdb.num-files-at-level0")).
+            isEqualTo("0");
+        // Making sure there are some L1 files.
+        // Here we only use != 0 instead of a specific number
+        // as we don't want the test make any assumption on
+        // how compaction works.
+        assertThat(
+            db.getProperty("rocksdb.num-files-at-level1")).
+            isNotEqualTo("0");
+        // Because we only compacted those keys we issued
+        // in this round, there shouldn't be any L1 -> L2
+        // compaction.  So we expect zero L2 files here.
+        assertThat(
+            db.getProperty("rocksdb.num-files-at-level2")).
+            isEqualTo("0");
       }
     } finally {
       if (db != null) {
@@ -662,6 +687,14 @@ public class RocksDBTest {
     List<ColumnFamilyHandle> columnFamilyHandles =
         new ArrayList<>();
     try {
+      final int NUM_KEYS_PER_L0_FILE = 100;
+      final int KEY_SIZE = 20;
+      final int VALUE_SIZE = 300;
+      final int L0_FILE_SIZE =
+          NUM_KEYS_PER_L0_FILE * (KEY_SIZE + VALUE_SIZE);
+      final int NUM_L0_FILES = 10;
+      final int TEST_SCALE = 5;
+      final int KEY_INTERVAL = 100;
       opt = new DBOptions().
           setCreateIfMissing(true).
           setCreateMissingColumnFamilies(true);
@@ -672,62 +705,73 @@ public class RocksDBTest {
       columnFamilyDescriptors.add(new ColumnFamilyDescriptor(
           "new_cf".getBytes(),
           new ColumnFamilyOptions().
-              setDisableAutoCompactions(true).
               setCompactionStyle(CompactionStyle.LEVEL).
-              setNumLevels(4).
-              setWriteBufferSize(100 << 10).
-              setLevelZeroFileNumCompactionTrigger(3).
-              setTargetFileSizeBase(200 << 10).
+              setNumLevels(5).
+              // a slightly bigger write buffer than L0 file
+              // so that we can ensure manual flush always
+              // go before background flush happens.
+              setWriteBufferSize(L0_FILE_SIZE * 2).
+              // Disable auto L0 -> L1 compaction
+              setLevelZeroFileNumCompactionTrigger(20).
+              setTargetFileSizeBase(L0_FILE_SIZE * 100).
               setTargetFileSizeMultiplier(1).
-              setMaxBytesForLevelBase(500 << 10).
-              setMaxBytesForLevelMultiplier(1).
-              setDisableAutoCompactions(false)));
+              // To disable auto compaction
+              setMaxBytesForLevelBase(NUM_L0_FILES * L0_FILE_SIZE * 100).
+              setMaxBytesForLevelMultiplier(2).
+              setDisableAutoCompactions(true)));
       // open database
       db = RocksDB.open(opt,
           dbFolder.getRoot().getAbsolutePath(),
           columnFamilyDescriptors,
           columnFamilyHandles);
       // fill database with key/value pairs
-      byte[] b = new byte[10000];
-      for (int i = 0; i < 200; i++) {
-        rand.nextBytes(b);
-        db.put(columnFamilyHandles.get(1),
-            String.valueOf(i).getBytes(), b);
-      }
-      db.flush(new FlushOptions().setWaitForFlush(true),
-          columnFamilyHandles.get(1));
-      // free column families
-      for (ColumnFamilyHandle handle : columnFamilyHandles) {
-        handle.dispose();
-      }
-      // clear column family handles for reopen
-      columnFamilyHandles.clear();
-      db.close();
-      columnFamilyDescriptors.get(1).
-          columnFamilyOptions().
-          setTargetFileSizeBase(Long.MAX_VALUE).
-          setTargetFileSizeMultiplier(1).
-          setMaxBytesForLevelBase(Long.MAX_VALUE).
-          setMaxBytesForLevelMultiplier(1).
-          setDisableAutoCompactions(true);
-      // reopen database
-      db = RocksDB.open(opt,
-          dbFolder.getRoot().getAbsolutePath(),
-          columnFamilyDescriptors,
-          columnFamilyHandles);
-      // compact new column family
-      db.compactRange(columnFamilyHandles.get(1), true, 0, 0);
-      // check if new column family is compacted to level zero
-      for (int i = 0; i < 4; i++) {
-        if (i == 0) {
-          assertThat(db.getProperty(columnFamilyHandles.get(1),
-              "rocksdb.num-files-at-level" + i)).
-              isEqualTo("1");
-        } else {
-          assertThat(db.getProperty(columnFamilyHandles.get(1),
-              "rocksdb.num-files-at-level" + i)).
-              isEqualTo("0");
+      byte[] value = new byte[VALUE_SIZE];
+      int int_key = 0;
+      for (int round = 0; round < 5; ++round) {
+        int initial_key = int_key;
+        for (int f = 1; f <= NUM_L0_FILES; ++f) {
+          for (int i = 0; i < NUM_KEYS_PER_L0_FILE; ++i) {
+            int_key += KEY_INTERVAL;
+            rand.nextBytes(value);
+
+            db.put(columnFamilyHandles.get(1),
+                   String.format("%020d", int_key).getBytes(),
+                   value);
+          }
+          db.flush(new FlushOptions().setWaitForFlush(true),
+                   columnFamilyHandles.get(1));
+          // Make sure we do create one more L0 files.
+          assertThat(
+              db.getProperty(columnFamilyHandles.get(1),
+                             "rocksdb.num-files-at-level0")).
+              isEqualTo("" + f);
         }
+
+        // Compact all L0 files we just created
+        db.compactRange(
+            columnFamilyHandles.get(1),
+            String.format("%020d", initial_key).getBytes(),
+            String.format("%020d", int_key - 1).getBytes());
+        // Making sure there isn't any L0 files.
+        assertThat(
+            db.getProperty(columnFamilyHandles.get(1),
+                           "rocksdb.num-files-at-level0")).
+            isEqualTo("0");
+        // Making sure there are some L1 files.
+        // Here we only use != 0 instead of a specific number
+        // as we don't want the test make any assumption on
+        // how compaction works.
+        assertThat(
+            db.getProperty(columnFamilyHandles.get(1),
+                           "rocksdb.num-files-at-level1")).
+            isNotEqualTo("0");
+        // Because we only compacted those keys we issued
+        // in this round, there shouldn't be any L1 -> L2
+        // compaction.  So we expect zero L2 files here.
+        assertThat(
+            db.getProperty(columnFamilyHandles.get(1),
+                           "rocksdb.num-files-at-level2")).
+            isEqualTo("0");
       }
     } finally {
       for (ColumnFamilyHandle handle : columnFamilyHandles) {