fix some misspellings

Summary:
PTAL ajkr
Closes https://github.com/facebook/rocksdb/pull/2750

Differential Revision: D5648052

Pulled By: ajkr

fbshipit-source-id: 7cd1ddd61364d5a55a10fdd293fa74b2bf89dd98

db/db_impl_write.cc

@@ -1081,7 +1081,7 @@ Status DBImpl::SwitchMemtable(ColumnFamilyData* cfd, WriteContext* context) {
   SuperVersion* new_superversion = nullptr;
   const MutableCFOptions mutable_cf_options = *cfd->GetLatestMutableCFOptions();
 
-  // Set current_memtble_info for memtable sealed callback
+  // Set memtable_info for memtable sealed callback
 #ifndef ROCKSDB_LITE
   MemTableInfo memtable_info;
   memtable_info.cf_name = cfd->GetName();

options/cf_options.h

@@ -83,7 +83,7 @@ struct ImmutableCFOptions {
   bool advise_random_on_open;
 
   // This options is required by PlainTableReader. May need to move it
-  // to PlainTalbeOptions just like bloom_bits_per_key
+  // to PlainTableOptions just like bloom_bits_per_key
   uint32_t bloom_locality;
 
   bool purge_redundant_kvs_while_flush;

utilities/blob_db/blob_db_test.cc

@@ -617,7 +617,7 @@ TEST_F(BlobDBTest, GCAfterOverwriteKeys) {
   VerifyDB(data);
 }
 
-TEST_F(BlobDBTest, GCRelocateKeyWhileOverwritting) {
+TEST_F(BlobDBTest, GCRelocateKeyWhileOverwriting) {
   Random rnd(301);
   BlobDBOptions bdb_options;
   bdb_options.disable_background_tasks = true;
@@ -650,7 +650,7 @@ TEST_F(BlobDBTest, GCRelocateKeyWhileOverwritting) {
   VerifyDB({{"foo", "v2"}});
 }
 
-TEST_F(BlobDBTest, GCExpiredKeyWhileOverwritting) {
+TEST_F(BlobDBTest, GCExpiredKeyWhileOverwriting) {
   Random rnd(301);
   Options options;
   options.env = mock_env_.get();

utilities/transactions/pessimistic_transaction_db.cc

@@ -332,7 +332,7 @@ Transaction* PessimisticTransactionDB::BeginInternalTransaction(
 
 // All user Put, Merge, Delete, and Write requests must be intercepted to make
 // sure that they lock all keys that they are writing to avoid causing conflicts
-// with any concurent transactions. The easiest way to do this is to wrap all
+// with any concurrent transactions. The easiest way to do this is to wrap all
 // write operations in a transaction.
 //
 // Put(), Merge(), and Delete() only lock a single key per call.  Write() will