db_basic_bench fix for DB object cleanup (#9939)

Summary:
Use `unique_ptr<DB>` to make sure the DB object is deleted. Previously it was not, which led to accumulating file descriptors for deleted directories because a `DBImpl::db_dir_` from each test remained alive.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9939

Test Plan: run `lsof -p $(pidof db_basic_bench)` while benchmark runs; verify no FDs for deleted directories.

Reviewed By: jay-zhuang

Differential Revision: D36108761

Pulled By: ajkr

fbshipit-source-id: cfe02646b038a445af7d5db8989eb1f40d658359

microbench/db_basic_bench.cc

@@ -118,7 +118,8 @@ class KeyGenerator {
   }
 };
 
-static void SetupDB(benchmark::State& state, Options& options, DB** dpptr,
+static void SetupDB(benchmark::State& state, Options& options,
+                    std::unique_ptr<DB>* db,
                     const std::string& test_name = "") {
   options.create_if_missing = true;
   auto env = Env::Default();
@@ -132,15 +133,17 @@ static void SetupDB(benchmark::State& state, Options& options, DB** dpptr,
       db_path + kFilePathSeparator + test_name + std::to_string(getpid());
   DestroyDB(db_name, options);
 
-  s = DB::Open(options, db_name, dpptr);
+  DB* db_ptr = nullptr;
+  s = DB::Open(options, db_name, &db_ptr);
   if (!s.ok()) {
     state.SkipWithError(s.ToString().c_str());
     return;
   }
+  db->reset(db_ptr);
 }
 
-static void TeardownDB(benchmark::State& state, DB* db, const Options& options,
-                       KeyGenerator& kg) {
+static void TeardownDB(benchmark::State& state, const std::unique_ptr<DB>& db,
+                       const Options& options, KeyGenerator& kg) {
   char min_buff[256], max_buff[256];
   const Range r(kg.MinKey(min_buff), kg.MaxKey(max_buff));
   uint64_t size;
@@ -160,7 +163,7 @@ static void TeardownDB(benchmark::State& state, DB* db, const Options& options,
 
 static void DBOpen(benchmark::State& state) {
   // create DB
-  DB* db = nullptr;
+  std::unique_ptr<DB> db;
   Options options;
   SetupDB(state, options, &db, "DBOpen");
 
@@ -172,12 +175,17 @@ static void DBOpen(benchmark::State& state) {
   auto rnd = Random(123);
 
   for (auto _ : state) {
-    Status s = DB::Open(options, db_name, &db);
-    if (!s.ok()) {
-      state.SkipWithError(s.ToString().c_str());
+    {
+      DB* db_ptr = nullptr;
+      Status s = DB::Open(options, db_name, &db_ptr);
+      if (!s.ok()) {
+        state.SkipWithError(s.ToString().c_str());
+      }
+      db.reset(db_ptr);
     }
     state.PauseTiming();
     auto wo = WriteOptions();
+    Status s;
     for (int i = 0; i < 2; i++) {
       for (int j = 0; j < 100; j++) {
         s = db->Put(wo, rnd.RandomString(10), rnd.RandomString(100));
@@ -204,7 +212,7 @@ BENCHMARK(DBOpen)->Iterations(200);  // specify iteration number as the db size
 
 static void DBClose(benchmark::State& state) {
   // create DB
-  DB* db;
+  std::unique_ptr<DB> db;
   Options options;
   SetupDB(state, options, &db, "DBClose");
 
@@ -217,11 +225,16 @@ static void DBClose(benchmark::State& state) {
 
   for (auto _ : state) {
     state.PauseTiming();
-    Status s = DB::Open(options, db_name, &db);
-    if (!s.ok()) {
-      state.SkipWithError(s.ToString().c_str());
+    {
+      DB* db_ptr = nullptr;
+      Status s = DB::Open(options, db_name, &db_ptr);
+      if (!s.ok()) {
+        state.SkipWithError(s.ToString().c_str());
+      }
+      db.reset(db_ptr);
     }
     auto wo = WriteOptions();
+    Status s;
     for (int i = 0; i < 2; i++) {
       for (int j = 0; j < 100; j++) {
         s = db->Put(wo, rnd.RandomString(10), rnd.RandomString(100));
@@ -255,7 +268,7 @@ static void DBPut(benchmark::State& state) {
   uint64_t key_num = max_data / per_key_size;
 
   // setup DB
-  static DB* db = nullptr;
+  static std::unique_ptr<DB> db = nullptr;
   Options options;
   if (enable_statistics) {
     options.statistics = CreateDBStatistics();
@@ -284,7 +297,7 @@ static void DBPut(benchmark::State& state) {
   }
 
   if (state.thread_index() == 0) {
-    auto db_full = static_cast_with_check<DBImpl>(db);
+    auto db_full = static_cast_with_check<DBImpl>(db.get());
     Status s = db_full->WaitForCompact(true);
     if (!s.ok()) {
       state.SkipWithError(s.ToString().c_str());
@@ -332,7 +345,7 @@ static void ManualCompaction(benchmark::State& state) {
   uint64_t key_num = max_data / per_key_size;
 
   // setup DB
-  static DB* db;
+  static std::unique_ptr<DB> db;
   Options options;
   if (enable_statistics) {
     options.statistics = CreateDBStatistics();
@@ -391,7 +404,7 @@ static void ManualCompaction(benchmark::State& state) {
   }
 
   if (state.thread_index() == 0) {
-    auto db_full = static_cast_with_check<DBImpl>(db);
+    auto db_full = static_cast_with_check<DBImpl>(db.get());
     s = db_full->WaitForCompact(true);
     if (!s.ok()) {
       state.SkipWithError(s.ToString().c_str());
@@ -453,7 +466,7 @@ static void ManualFlush(benchmark::State& state) {
   bool enable_statistics = true;
 
   // setup DB
-  static DB* db;
+  static std::unique_ptr<DB> db;
   Options options;
   if (enable_statistics) {
     options.statistics = CreateDBStatistics();
@@ -489,7 +502,7 @@ static void ManualFlush(benchmark::State& state) {
   }
 
   if (state.thread_index() == 0) {
-    auto db_full = static_cast_with_check<DBImpl>(db);
+    auto db_full = static_cast_with_check<DBImpl>(db.get());
     Status s = db_full->WaitForCompact(true);
     if (!s.ok()) {
       state.SkipWithError(s.ToString().c_str());
@@ -529,7 +542,7 @@ static void DBGet(benchmark::State& state) {
   uint64_t key_num = max_data / per_key_size;
 
   // setup DB
-  static DB* db;
+  static std::unique_ptr<DB> db;
   Options options;
   if (enable_statistics) {
     options.statistics = CreateDBStatistics();
@@ -573,7 +586,7 @@ static void DBGet(benchmark::State& state) {
       state.SkipWithError(s.ToString().c_str());
     }
 
-    auto db_full = static_cast_with_check<DBImpl>(db);
+    auto db_full = static_cast_with_check<DBImpl>(db.get());
     s = db_full->WaitForCompact(true);
     if (!s.ok()) {
       state.SkipWithError(s.ToString().c_str());
@@ -648,7 +661,7 @@ BENCHMARK(DBGet)->Threads(8)->Iterations(kDBGetNum / 8)->Apply(DBGetArguments);
 
 static void SimpleGetWithPerfContext(benchmark::State& state) {
   // setup DB
-  static DB* db;
+  static std::unique_ptr<DB> db;
   std::string db_name;
   Options options;
   options.create_if_missing = true;
@@ -668,10 +681,14 @@ static void SimpleGetWithPerfContext(benchmark::State& state) {
     db_name = db_path + "/simple_get_" + std::to_string(getpid());
     DestroyDB(db_name, options);
 
-    s = DB::Open(options, db_name, &db);
-    if (!s.ok()) {
-      state.SkipWithError(s.ToString().c_str());
-      return;
+    {
+      DB* db_ptr = nullptr;
+      s = DB::Open(options, db_name, &db_ptr);
+      if (!s.ok()) {
+        state.SkipWithError(s.ToString().c_str());
+        return;
+      }
+      db.reset(db_ptr);
     }
     // load db
     auto wo = WriteOptions();
@@ -682,7 +699,7 @@ static void SimpleGetWithPerfContext(benchmark::State& state) {
         state.SkipWithError(s.ToString().c_str());
       }
     }
-    auto db_full = static_cast_with_check<DBImpl>(db);
+    auto db_full = static_cast_with_check<DBImpl>(db.get());
     s = db_full->WaitForCompact(true);
     if (!s.ok()) {
       state.SkipWithError(s.ToString().c_str());
@@ -858,7 +875,7 @@ static void IteratorSeek(benchmark::State& state) {
   uint64_t key_num = max_data / per_key_size;
 
   // setup DB
-  static DB* db;
+  static std::unique_ptr<DB> db;
   Options options;
   if (enable_statistics) {
     options.statistics = CreateDBStatistics();
@@ -894,7 +911,7 @@ static void IteratorSeek(benchmark::State& state) {
       state.SkipWithError(s.ToString().c_str());
     }
 
-    auto db_full = static_cast_with_check<DBImpl>(db);
+    auto db_full = static_cast_with_check<DBImpl>(db.get());
     s = db_full->WaitForCompact(true);
     if (!s.ok()) {
       state.SkipWithError(s.ToString().c_str());
@@ -961,7 +978,7 @@ static void IteratorNext(benchmark::State& state) {
   uint64_t key_num = max_data / per_key_size;
 
   // setup DB
-  static DB* db;
+  static std::unique_ptr<DB> db;
   Options options;
   options.compaction_style = compaction_style;
 
@@ -987,7 +1004,7 @@ static void IteratorNext(benchmark::State& state) {
       state.SkipWithError(s.ToString().c_str());
     }
 
-    auto db_full = static_cast_with_check<DBImpl>(db);
+    auto db_full = static_cast_with_check<DBImpl>(db.get());
     s = db_full->WaitForCompact(true);
     if (!s.ok()) {
       state.SkipWithError(s.ToString().c_str());
@@ -1036,7 +1053,7 @@ BENCHMARK(IteratorNext)
 
 static void IteratorNextWithPerfContext(benchmark::State& state) {
   // setup DB
-  static DB* db;
+  static std::unique_ptr<DB> db;
   Options options;
 
   auto rnd = Random(301 + state.thread_index());
@@ -1053,7 +1070,7 @@ static void IteratorNextWithPerfContext(benchmark::State& state) {
         state.SkipWithError(s.ToString().c_str());
       }
     }
-    auto db_full = static_cast_with_check<DBImpl>(db);
+    auto db_full = static_cast_with_check<DBImpl>(db.get());
     Status s = db_full->WaitForCompact(true);
     if (!s.ok()) {
       state.SkipWithError(s.ToString().c_str());
@@ -1128,7 +1145,7 @@ static void IteratorPrev(benchmark::State& state) {
   uint64_t key_num = max_data / per_key_size;
 
   // setup DB
-  static DB* db;
+  static std::unique_ptr<DB> db;
   std::string db_name;
   Options options;
   options.compaction_style = compaction_style;
@@ -1155,7 +1172,7 @@ static void IteratorPrev(benchmark::State& state) {
       state.SkipWithError(s.ToString().c_str());
     }
 
-    auto db_full = static_cast_with_check<DBImpl>(db);
+    auto db_full = static_cast_with_check<DBImpl>(db.get());
     s = db_full->WaitForCompact(true);
     if (!s.ok()) {
       state.SkipWithError(s.ToString().c_str());
@@ -1212,7 +1229,7 @@ static void PrefixSeek(benchmark::State& state) {
   uint64_t key_num = max_data / per_key_size;
 
   // setup DB
-  static DB* db;
+  static std::unique_ptr<DB> db;
   Options options;
   if (enable_statistics) {
     options.statistics = CreateDBStatistics();
@@ -1249,7 +1266,7 @@ static void PrefixSeek(benchmark::State& state) {
       state.SkipWithError(s.ToString().c_str());
     }
 
-    auto db_full = static_cast_with_check<DBImpl>(db);
+    auto db_full = static_cast_with_check<DBImpl>(db.get());
     s = db_full->WaitForCompact(true);
     if (!s.ok()) {
       state.SkipWithError(s.ToString().c_str());