Function BM_LogAndApply

src/leveldb/db/db_test.cc:2238–2288

}

void BM_LogAndApply(int iters, int num_base_files) {
  std::string dbname = test::TmpDir() + "/leveldb_test_benchmark";
  DestroyDB(dbname, Options());

  DB* db = nullptr;
  Options opts;
  opts.create_if_missing = true;
  Status s = DB::Open(opts, dbname, &db);
  ASSERT_OK(s);
  ASSERT_TRUE(db != nullptr);

  delete db;
  db = nullptr;

  Env* env = Env::Default();

  port::Mutex mu;
  MutexLock l(&mu);

  InternalKeyComparator cmp(BytewiseComparator());
  Options options;
  VersionSet vset(dbname, &options, nullptr, &cmp);
  bool save_manifest;
  ASSERT_OK(vset.Recover(&save_manifest));
  VersionEdit vbase;
  uint64_t fnum = 1;
  for (int i = 0; i < num_base_files; i++) {
    InternalKey start(MakeKey(2 * fnum), 1, kTypeValue);
    InternalKey limit(MakeKey(2 * fnum + 1), 1, kTypeDeletion);
    vbase.AddFile(2, fnum++, 1 /* file size */, start, limit);
  }
  ASSERT_OK(vset.LogAndApply(&vbase, &mu));

  uint64_t start_micros = env->NowMicros();

  for (int i = 0; i < iters; i++) {
    VersionEdit vedit;
    vedit.DeleteFile(2, fnum);
    InternalKey start(MakeKey(2 * fnum), 1, kTypeValue);
    InternalKey limit(MakeKey(2 * fnum + 1), 1, kTypeDeletion);
    vedit.AddFile(2, fnum++, 1 /* file size */, start, limit);
    vset.LogAndApply(&vedit, &mu);
  }
  uint64_t stop_micros = env->NowMicros();
  unsigned int us = stop_micros - start_micros;
  char buf[16];
  snprintf(buf, sizeof(buf), "%d", num_base_files);
  fprintf(stderr,
          "BM_LogAndApply/%-6s   %8d iters : %9u us (%7.0f us / iter)\n", buf,
          iters, us, ((float)us) / iters);
}

}  // namespace leveldb