Remove the support of setting CompressionOptions.parallel_threads from string for now (#6782)

Summary:
The current way of implementing CompressionOptions.parallel_threads introduces a format change. We plan to change CompressionOptions's serailization format to a new JSON-like format, which would be another format change. We would like to consolidate the two format changes into one, rather than making some users to change twice. Hold CompressionOptions.parallel_threads from being supported by option string for now. Will add it back after the general CompressionOptions's format change.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6782

Test Plan: Run all existing tests.

Reviewed By: zhichao-cao

Differential Revision: D21338614

fbshipit-source-id: bca2dac3cb37d4e6e64b52cbbe8ea749cd848685

db/db_options_test.cc

@@ -920,7 +920,7 @@ TEST_F(DBOptionsTest, ChangeCompression) {
   compacted = false;
   ASSERT_OK(dbfull()->SetOptions(
       {{"bottommost_compression", "kSnappyCompression"},
-       {"bottommost_compression_opts", "0:6:0:0:0:4:true"}}));
+       {"bottommost_compression_opts", "0:6:0:0:4:true"}}));
   ASSERT_OK(Put("foo", "foofoofoo"));
   ASSERT_OK(Put("bar", "foofoofoo"));
   ASSERT_OK(Flush());
@@ -931,7 +931,7 @@ TEST_F(DBOptionsTest, ChangeCompression) {
   ASSERT_TRUE(compacted);
   ASSERT_EQ(CompressionType::kSnappyCompression, compression_used);
   ASSERT_EQ(6, compression_opt_used.level);
-  ASSERT_EQ(4u, compression_opt_used.parallel_threads);
+  // Right now parallel_level is not yet allowed to be changed.
 
   SyncPoint::GetInstance()->DisableProcessing();
 }

options/cf_options.cc

@@ -94,17 +94,10 @@ static Status ParseCompressionOptions(const std::string& value,
         ParseInt(value.substr(start, value.size() - start));
     end = value.find(':', start);
   }
-  // parallel_threads is optional for backwards compatibility
-  if (end != std::string::npos) {
-    start = end + 1;
-    if (start >= value.size()) {
-      return Status::InvalidArgument(
-          "unable to parse the specified CF option " + name);
-    }
-    compression_opts.parallel_threads =
-        ParseInt(value.substr(start, value.size() - start));
-    end = value.find(':', start);
-  }
+  // parallel_threads is not serialized with this format.
+  // We plan to upgrade the format to a JSON-like format.
+  compression_opts.parallel_threads = CompressionOptions().parallel_threads;
+
   // enabled is optional for backwards compatibility
   if (end != std::string::npos) {
     start = end + 1;

options/options_settable_test.cc

@@ -454,8 +454,8 @@ TEST_F(OptionsSettableTest, ColumnFamilyOptionsAllFieldsSettable) {
       "max_bytes_for_level_multiplier=60;"
       "memtable_factory=SkipListFactory;"
       "compression=kNoCompression;"
-      "compression_opts=5:6:7:8:9:10:true;"
-      "bottommost_compression_opts=4:5:6:7:8:9:true;"
+      "compression_opts=5:6:7:8:9:true;"
+      "bottommost_compression_opts=4:5:6:7:8:true;"
       "bottommost_compression=kDisableCompressionOption;"
       "level0_stop_writes_trigger=33;"
       "num_levels=99;"

options/options_test.cc

@@ -62,8 +62,8 @@ TEST_F(OptionsTest, GetOptionsFromMapTest) {
        "kZSTD:"
        "kZSTDNotFinalCompression"},
       {"bottommost_compression", "kLZ4Compression"},
-      {"bottommost_compression_opts", "5:6:7:8:9:10:true"},
-      {"compression_opts", "4:5:6:7:8:9:true"},
+      {"bottommost_compression_opts", "5:6:7:8:10:true"},
+      {"compression_opts", "4:5:6:7:8:true"},
       {"num_levels", "8"},
       {"level0_file_num_compaction_trigger", "8"},
       {"level0_slowdown_writes_trigger", "9"},
@@ -175,15 +175,17 @@ TEST_F(OptionsTest, GetOptionsFromMapTest) {
   ASSERT_EQ(new_cf_opt.compression_opts.strategy, 6);
   ASSERT_EQ(new_cf_opt.compression_opts.max_dict_bytes, 7u);
   ASSERT_EQ(new_cf_opt.compression_opts.zstd_max_train_bytes, 8u);
-  ASSERT_EQ(new_cf_opt.compression_opts.parallel_threads, 9u);
+  ASSERT_EQ(new_cf_opt.compression_opts.parallel_threads,
+            CompressionOptions().parallel_threads);
   ASSERT_EQ(new_cf_opt.compression_opts.enabled, true);
   ASSERT_EQ(new_cf_opt.bottommost_compression, kLZ4Compression);
   ASSERT_EQ(new_cf_opt.bottommost_compression_opts.window_bits, 5);
   ASSERT_EQ(new_cf_opt.bottommost_compression_opts.level, 6);
   ASSERT_EQ(new_cf_opt.bottommost_compression_opts.strategy, 7);
   ASSERT_EQ(new_cf_opt.bottommost_compression_opts.max_dict_bytes, 8u);
-  ASSERT_EQ(new_cf_opt.bottommost_compression_opts.zstd_max_train_bytes, 9u);
-  ASSERT_EQ(new_cf_opt.bottommost_compression_opts.parallel_threads, 10u);
+  ASSERT_EQ(new_cf_opt.bottommost_compression_opts.zstd_max_train_bytes, 10u);
+  ASSERT_EQ(new_cf_opt.bottommost_compression_opts.parallel_threads,
+            CompressionOptions().parallel_threads);
   ASSERT_EQ(new_cf_opt.bottommost_compression_opts.enabled, true);
   ASSERT_EQ(new_cf_opt.num_levels, 8);
   ASSERT_EQ(new_cf_opt.level0_file_num_compaction_trigger, 8);
@@ -1297,8 +1299,8 @@ TEST_F(OptionsOldApiTest, GetOptionsFromMapTest) {
        "kZSTD:"
        "kZSTDNotFinalCompression"},
       {"bottommost_compression", "kLZ4Compression"},
-      {"bottommost_compression_opts", "5:6:7:8:9:10:true"},
-      {"compression_opts", "4:5:6:7:8:9:true"},
+      {"bottommost_compression_opts", "5:6:7:8:9:true"},
+      {"compression_opts", "4:5:6:7:8:true"},
       {"num_levels", "8"},
       {"level0_file_num_compaction_trigger", "8"},
       {"level0_slowdown_writes_trigger", "9"},
@@ -1402,7 +1404,8 @@ TEST_F(OptionsOldApiTest, GetOptionsFromMapTest) {
   ASSERT_EQ(new_cf_opt.compression_opts.strategy, 6);
   ASSERT_EQ(new_cf_opt.compression_opts.max_dict_bytes, 7u);
   ASSERT_EQ(new_cf_opt.compression_opts.zstd_max_train_bytes, 8u);
-  ASSERT_EQ(new_cf_opt.compression_opts.parallel_threads, 9u);
+  ASSERT_EQ(new_cf_opt.compression_opts.parallel_threads,
+            CompressionOptions().parallel_threads);
   ASSERT_EQ(new_cf_opt.compression_opts.enabled, true);
   ASSERT_EQ(new_cf_opt.bottommost_compression, kLZ4Compression);
   ASSERT_EQ(new_cf_opt.bottommost_compression_opts.window_bits, 5);
@@ -1410,7 +1413,8 @@ TEST_F(OptionsOldApiTest, GetOptionsFromMapTest) {
   ASSERT_EQ(new_cf_opt.bottommost_compression_opts.strategy, 7);
   ASSERT_EQ(new_cf_opt.bottommost_compression_opts.max_dict_bytes, 8u);
   ASSERT_EQ(new_cf_opt.bottommost_compression_opts.zstd_max_train_bytes, 9u);
-  ASSERT_EQ(new_cf_opt.bottommost_compression_opts.parallel_threads, 10u);
+  ASSERT_EQ(new_cf_opt.bottommost_compression_opts.parallel_threads,
+            CompressionOptions().parallel_threads);
   ASSERT_EQ(new_cf_opt.bottommost_compression_opts.enabled, true);
   ASSERT_EQ(new_cf_opt.num_levels, 8);
   ASSERT_EQ(new_cf_opt.level0_file_num_compaction_trigger, 8);