Remove redundant member var and set options (facebook#4631)

Summary:
In the past, both `DBImpl::atomic_flush_` and
`DBImpl::immutable_db_options_.atomic_flush` exist. However, we fail to set
`immutable_db_options_.atomic_flush`, but use `DBImpl::atomic_flush_` which is
set correctly. This does not lead to incorrect behavior, but is a duplicate of
information.

Since `immutable_db_options_` is always there and has `atomic_flush`, we should
use it as source of truth and remove `DBImpl::atomic_flush_`.
Pull Request resolved: facebook#4631

Differential Revision: D12928371

Pulled By: riversand963

fbshipit-source-id: f85a811959d3828aad4a3a1b05f71facf19c636d

db/db_filesnapshot.cc

@@ -86,7 +86,7 @@ Status DBImpl::GetLiveFiles(std::vector<std::string>& ret,
   if (flush_memtable) {
     // flush all dirty data to disk.
     Status status;
-    if (atomic_flush_) {
+    if (immutable_db_options_.atomic_flush) {
       autovector<ColumnFamilyData*> cfds;
       SelectColumnFamiliesForAtomicFlush(&cfds);
       mutex_.Unlock();

db/db_impl.cc

@@ -220,7 +220,6 @@ DBImpl::DBImpl(const DBOptions& options, const std::string& dbname,
       preserve_deletes_(options.preserve_deletes),
       closed_(false),
       error_handler_(this, immutable_db_options_, &mutex_),
-      atomic_flush_(options.atomic_flush),
       atomic_flush_commit_in_progress_(false) {
   // !batch_per_trx_ implies seq_per_batch_ because it is only unset for
   // WriteUnprepared, which should use seq_per_batch_.
@@ -309,7 +308,7 @@ Status DBImpl::ResumeImpl() {
     FlushOptions flush_opts;
     // We allow flush to stall write since we are trying to resume from error.
     flush_opts.allow_write_stall = true;
-    if (atomic_flush_) {
+    if (immutable_db_options_.atomic_flush) {
       autovector<ColumnFamilyData*> cfds;
       SelectColumnFamiliesForAtomicFlush(&cfds);
       mutex_.Unlock();
@@ -401,7 +400,7 @@ void DBImpl::CancelAllBackgroundWork(bool wait) {
   if (!shutting_down_.load(std::memory_order_acquire) &&
       has_unpersisted_data_.load(std::memory_order_relaxed) &&
       !mutable_db_options_.avoid_flush_during_shutdown) {
-    if (atomic_flush_) {
+    if (immutable_db_options_.atomic_flush) {
       autovector<ColumnFamilyData*> cfds;
       SelectColumnFamiliesForAtomicFlush(&cfds);
       mutex_.Unlock();
@@ -3130,7 +3129,7 @@ Status DBImpl::IngestExternalFile(
       TEST_SYNC_POINT_CALLBACK("DBImpl::IngestExternalFile:NeedFlush",
                                &need_flush);
       if (status.ok() && need_flush) {
-        if (atomic_flush_) {
+        if (immutable_db_options_.atomic_flush) {
           mutex_.Unlock();
           autovector<ColumnFamilyData*> cfds;
           SelectColumnFamiliesForAtomicFlush(&cfds);

db/db_impl.h

@@ -1611,9 +1611,6 @@ class DBImpl : public DB {
 
   ErrorHandler error_handler_;
 
-  // True if DB enables atomic flush.
-  bool atomic_flush_;
-
   // True if the DB is committing atomic flush.
   // TODO (yanqin) the current impl assumes that the entire DB belongs to
   // a single atomic flush group. In the future we need to add a new class

db/db_impl_compaction_flush.cc

@@ -211,7 +211,7 @@ Status DBImpl::FlushMemTableToOutputFile(
 Status DBImpl::FlushMemTablesToOutputFiles(
     const autovector<BGFlushArg>& bg_flush_args, bool* made_progress,
     JobContext* job_context, LogBuffer* log_buffer) {
-  if (atomic_flush_) {
+  if (immutable_db_options_.atomic_flush) {
     return AtomicFlushMemTablesToOutputFiles(bg_flush_args, made_progress,
                                              job_context, log_buffer);
   }
@@ -566,7 +566,7 @@ Status DBImpl::CompactRange(const CompactRangeOptions& options,
   if (flush_needed) {
     FlushOptions fo;
     fo.allow_write_stall = options.allow_write_stall;
-    if (atomic_flush_) {
+    if (immutable_db_options_.atomic_flush) {
       autovector<ColumnFamilyData*> cfds;
       SelectColumnFamiliesForAtomicFlush(&cfds);
       s = AtomicFlushMemTables(cfds, fo, FlushReason::kManualCompaction,
@@ -1196,7 +1196,7 @@ Status DBImpl::Flush(const FlushOptions& flush_options,
   ROCKS_LOG_INFO(immutable_db_options_.info_log, "[%s] Manual flush start.",
                  cfh->GetName().c_str());
   Status s;
-  if (atomic_flush_) {
+  if (immutable_db_options_.atomic_flush) {
     s = AtomicFlushMemTables({cfh->cfd()}, flush_options,
                              FlushReason::kManualFlush);
   } else {
@@ -1212,7 +1212,7 @@ Status DBImpl::Flush(const FlushOptions& flush_options,
 Status DBImpl::Flush(const FlushOptions& flush_options,
                      const std::vector<ColumnFamilyHandle*>& column_families) {
   Status s;
-  if (!atomic_flush_) {
+  if (!immutable_db_options_.atomic_flush) {
     for (auto cfh : column_families) {
       s = Flush(flush_options, cfh);
       if (!s.ok()) {

db/db_impl_write.cc

@@ -1029,7 +1029,7 @@ void DBImpl::SelectColumnFamiliesForAtomicFlush(
 
 // Assign sequence number for atomic flush.
 void DBImpl::AssignAtomicFlushSeq(const autovector<ColumnFamilyData*>& cfds) {
-  assert(atomic_flush_);
+  assert(immutable_db_options_.atomic_flush);
   auto seq = versions_->LastSequence();
   for (auto cfd : cfds) {
     cfd->imm()->AssignAtomicFlushSeq(seq);
@@ -1085,7 +1085,7 @@ Status DBImpl::SwitchWAL(WriteContext* write_context) {
   // no need to refcount because drop is happening in write thread, so can't
   // happen while we're in the write thread
   autovector<ColumnFamilyData*> cfds;
-  if (atomic_flush_) {
+  if (immutable_db_options_.atomic_flush) {
     SelectColumnFamiliesForAtomicFlush(&cfds);
   } else {
     for (auto cfd : *versions_->GetColumnFamilySet()) {
@@ -1106,7 +1106,7 @@ Status DBImpl::SwitchWAL(WriteContext* write_context) {
     }
   }
   if (status.ok()) {
-    if (atomic_flush_) {
+    if (immutable_db_options_.atomic_flush) {
       AssignAtomicFlushSeq(cfds);
     }
     for (auto cfd : cfds) {
@@ -1139,7 +1139,7 @@ Status DBImpl::HandleWriteBufferFull(WriteContext* write_context) {
   // no need to refcount because drop is happening in write thread, so can't
   // happen while we're in the write thread
   autovector<ColumnFamilyData*> cfds;
-  if (atomic_flush_) {
+  if (immutable_db_options_.atomic_flush) {
     SelectColumnFamiliesForAtomicFlush(&cfds);
   } else {
     ColumnFamilyData* cfd_picked = nullptr;
@@ -1176,7 +1176,7 @@ Status DBImpl::HandleWriteBufferFull(WriteContext* write_context) {
     }
   }
   if (status.ok()) {
-    if (atomic_flush_) {
+    if (immutable_db_options_.atomic_flush) {
       AssignAtomicFlushSeq(cfds);
     }
     for (const auto cfd : cfds) {
@@ -1307,7 +1307,7 @@ Status DBImpl::ThrottleLowPriWritesIfNeeded(const WriteOptions& write_options,
 
 Status DBImpl::ScheduleFlushes(WriteContext* context) {
   autovector<ColumnFamilyData*> cfds;
-  if (atomic_flush_) {
+  if (immutable_db_options_.atomic_flush) {
     SelectColumnFamiliesForAtomicFlush(&cfds);
     for (auto cfd : cfds) {
       cfd->Ref();
@@ -1333,7 +1333,7 @@ Status DBImpl::ScheduleFlushes(WriteContext* context) {
     }
   }
   if (status.ok()) {
-    if (atomic_flush_) {
+    if (immutable_db_options_.atomic_flush) {
       AssignAtomicFlushSeq(cfds);
     }
     FlushRequest flush_req;

options/db_options.cc

@@ -85,7 +85,8 @@ ImmutableDBOptions::ImmutableDBOptions(const DBOptions& options)
       allow_ingest_behind(options.allow_ingest_behind),
       preserve_deletes(options.preserve_deletes),
       two_write_queues(options.two_write_queues),
-      manual_wal_flush(options.manual_wal_flush) {
+      manual_wal_flush(options.manual_wal_flush),
+      atomic_flush(options.atomic_flush) {
 }
 
 void ImmutableDBOptions::Dump(Logger* log) const {

options/options_helper.cc

@@ -126,6 +126,7 @@ DBOptions BuildDBOptions(const ImmutableDBOptions& immutable_db_options,
       immutable_db_options.preserve_deletes;
   options.two_write_queues = immutable_db_options.two_write_queues;
   options.manual_wal_flush = immutable_db_options.manual_wal_flush;
+  options.atomic_flush = immutable_db_options.atomic_flush;
 
   return options;
 }