Build break fix.

Summary: Skip list now cannot estimate memory across allocators
consistently and hence triggers flush at different time. This breaks certain
unit tests.

The fix is to adopt key count instead of size for flush.

Test Plan: Ran test on dev box and mac (where it used to fail)

Reviewers: sdong

CC: leveldb@

Task ID: #9273334

Blame Rev:

db/db_test_util.cc

@@ -833,7 +833,7 @@ int DBTestBase::GetSstFileCount(std::string path) {
 // this will generate non-overlapping files since it keeps increasing key_idx
 void DBTestBase::GenerateNewFile(int cf, Random* rnd, int* key_idx,
                                  bool nowait) {
-  for (int i = 0; i < 100; i++) {
+  for (int i = 0; i < KNumKeysByGenerateNewFile; i++) {
     ASSERT_OK(Put(cf, Key(*key_idx), RandomString(rnd, (i == 99) ? 1 : 990)));
     (*key_idx)++;
   }
@@ -845,7 +845,7 @@ void DBTestBase::GenerateNewFile(int cf, Random* rnd, int* key_idx,
 
 // this will generate non-overlapping files since it keeps increasing key_idx
 void DBTestBase::GenerateNewFile(Random* rnd, int* key_idx, bool nowait) {
-  for (int i = 0; i < 100; i++) {
+  for (int i = 0; i < KNumKeysByGenerateNewFile; i++) {
     ASSERT_OK(Put(Key(*key_idx), RandomString(rnd, (i == 99) ? 1 : 990)));
     (*key_idx)++;
   }

db/db_test_util.h

@@ -710,6 +710,7 @@ class DBTestBase : public testing::Test {
   void GenerateNewFile(int fd, Random* rnd, int* key_idx, bool nowait = false);
 
   static const int kNumKeysByGenerateNewRandomFile;
+  static const int KNumKeysByGenerateNewFile = 100;
 
   void GenerateNewRandomFile(Random* rnd, bool nowait = false);
 

db/db_universal_compaction_test.cc

@@ -890,6 +890,8 @@ TEST_P(DBTestUniversalCompaction, UniversalCompactionFourPaths) {
   options.db_paths.emplace_back(dbname_ + "_2", 300 * 1024);
   options.db_paths.emplace_back(dbname_ + "_3", 500 * 1024);
   options.db_paths.emplace_back(dbname_ + "_4", 1024 * 1024 * 1024);
+  options.memtable_factory.reset(
+      new SpecialSkipListFactory(KNumKeysByGenerateNewFile - 1));
   options.compaction_style = kCompactionStyleUniversal;
   options.compaction_options_universal.size_ratio = 5;
   options.write_buffer_size = 110 << 10;  // 105KB