diff --git a/db/manual_compaction_test.cc b/db/manual_compaction_test.cc
index f31a50b81..3c342c454 100644
--- a/db/manual_compaction_test.cc
+++ b/db/manual_compaction_test.cc
@@ -19,7 +19,12 @@ using namespace rocksdb;
 
 namespace {
 
-const int kNumKeys = 1100000;
+// Reasoning: previously the number was 1100000. Since the keys are written to
+// the batch in one write each write will result into one SST file. each write
+// will result into one SST file. We reduced the write_buffer_size to 1K to
+// basically have the same effect with however less number of keys, which
+// results into less test runtime.
+const int kNumKeys = 1100;
 
 std::string Key1(int i) {
   char buf[100];
@@ -99,6 +104,7 @@ TEST_F(ManualCompactionTest, Test) {
   // specific scenario.
   rocksdb::DB* db;
   rocksdb::Options db_options;
+  db_options.write_buffer_size = 1024;
   db_options.create_if_missing = true;
   db_options.compression = rocksdb::kNoCompression;
   ASSERT_OK(rocksdb::DB::Open(db_options, dbname_, &db));