rocksdb/db/column_family_test.cc

//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
//  This source code is licensed under the BSD-style license found in the
//  LICENSE file in the root directory of this source tree. An additional grant
//  of patent rights can be found in the PATENTS file in the same directory.
//
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.

#include <algorithm>
#include <vector>
#include <string>

#include "db/db_impl.h"
#include "rocksdb/env.h"
#include "rocksdb/db.h"
#include "util/testharness.h"
#include "util/testutil.h"
#include "util/coding.h"
#include "utilities/merge_operators.h"

namespace rocksdb {

namespace {
std::string RandomString(Random* rnd, int len) {
  std::string r;
  test::RandomString(rnd, len, &r);
  return r;
}
}  // anonymous namespace

// counts how many operations were performed
class EnvCounter : public EnvWrapper {
 public:
  explicit EnvCounter(Env* base)
      : EnvWrapper(base), num_new_writable_file_(0) {}
  int GetNumberOfNewWritableFileCalls() {
    return num_new_writable_file_;
  }
  Status NewWritableFile(const std::string& f, unique_ptr<WritableFile>* r,
                         const EnvOptions& soptions) {
    ++num_new_writable_file_;
    return EnvWrapper::NewWritableFile(f, r, soptions);
  }

 private:
  int num_new_writable_file_;
};

class ColumnFamilyTest {
 public:
  ColumnFamilyTest() : rnd_(139) {
    env_ = new EnvCounter(Env::Default());
    dbname_ = test::TmpDir() + "/column_family_test";
    db_options_.create_if_missing = true;
    db_options_.env = env_;
    DestroyDB(dbname_, Options(db_options_, column_family_options_));
  }

  void Close() {
    for (auto h : handles_) {
      delete h;
    }
    handles_.clear();
    names_.clear();
    delete db_;
    db_ = nullptr;
  }

  Status TryOpen(std::vector<std::string> cf,
                 std::vector<ColumnFamilyOptions> options = {}) {
    std::vector<ColumnFamilyDescriptor> column_families;
    names_.clear();
    for (size_t i = 0; i < cf.size(); ++i) {
      column_families.push_back(ColumnFamilyDescriptor(
          cf[i], options.size() == 0 ? column_family_options_ : options[i]));
      names_.push_back(cf[i]);
    }
    return DB::Open(db_options_, dbname_, column_families, &handles_, &db_);
  }

  Status OpenReadOnly(std::vector<std::string> cf,
                         std::vector<ColumnFamilyOptions> options = {}) {
    std::vector<ColumnFamilyDescriptor> column_families;
    names_.clear();
    for (size_t i = 0; i < cf.size(); ++i) {
      column_families.push_back(ColumnFamilyDescriptor(
          cf[i], options.size() == 0 ? column_family_options_ : options[i]));
      names_.push_back(cf[i]);
    }
    return DB::OpenForReadOnly(db_options_, dbname_, column_families, &handles_,
                               &db_);
  }

  void AssertOpenReadOnly(std::vector<std::string> cf,
                    std::vector<ColumnFamilyOptions> options = {}) {
    ASSERT_OK(OpenReadOnly(cf, options));
  }


  void Open(std::vector<std::string> cf,
            std::vector<ColumnFamilyOptions> options = {}) {
    ASSERT_OK(TryOpen(cf, options));
  }

  void Open() {
    Open({"default"});
  }

  DBImpl* dbfull() { return reinterpret_cast<DBImpl*>(db_); }

  int GetProperty(int cf, std::string property) {
    std::string value;
    ASSERT_TRUE(dbfull()->GetProperty(handles_[cf], property, &value));
    return std::stoi(value);
  }

  void Destroy() {
    for (auto h : handles_) {
      delete h;
    }
    handles_.clear();
    names_.clear();
    delete db_;
    db_ = nullptr;
    ASSERT_OK(DestroyDB(dbname_, Options(db_options_, column_family_options_)));
  }

  void CreateColumnFamilies(
      const std::vector<std::string>& cfs,
      const std::vector<ColumnFamilyOptions> options = {}) {
    int cfi = handles_.size();
    handles_.resize(cfi + cfs.size());
    names_.resize(cfi + cfs.size());
    for (size_t i = 0; i < cfs.size(); ++i) {
      ASSERT_OK(db_->CreateColumnFamily(
          options.size() == 0 ? column_family_options_ : options[i], cfs[i],
          &handles_[cfi]));
      names_[cfi] = cfs[i];
      cfi++;
    }
  }

  void Reopen(const std::vector<ColumnFamilyOptions> options = {}) {
    std::vector<std::string> names;
    for (auto name : names_) {
      if (name != "") {
        names.push_back(name);
      }
    }
    Close();
    assert(options.size() == 0 || names.size() == options.size());
    Open(names, options);
  }

  void CreateColumnFamiliesAndReopen(const std::vector<std::string>& cfs) {
    CreateColumnFamilies(cfs);
    Reopen();
  }

  void DropColumnFamilies(const std::vector<int>& cfs) {
    for (auto cf : cfs) {
      ASSERT_OK(db_->DropColumnFamily(handles_[cf]));
      delete handles_[cf];
      handles_[cf] = nullptr;
      names_[cf] = "";
    }
  }

  void PutRandomData(int cf, int num, int key_value_size) {
    for (int i = 0; i < num; ++i) {
      // 10 bytes for key, rest is value
      ASSERT_OK(Put(cf, test::RandomKey(&rnd_, 10),
                    RandomString(&rnd_, key_value_size - 10)));
    }
  }

  void WaitForFlush(int cf) {
    ASSERT_OK(dbfull()->TEST_WaitForFlushMemTable(handles_[cf]));
  }

  void WaitForCompaction() { ASSERT_OK(dbfull()->TEST_WaitForCompact()); }

  Status Put(int cf, const std::string& key, const std::string& value) {
    return db_->Put(WriteOptions(), handles_[cf], Slice(key), Slice(value));
  }
  Status Merge(int cf, const std::string& key, const std::string& value) {
    return db_->Merge(WriteOptions(), handles_[cf], Slice(key), Slice(value));
  }
  Status Flush(int cf) {
    return db_->Flush(FlushOptions(), handles_[cf]);
  }

  std::string Get(int cf, const std::string& key) {
    ReadOptions options;
    options.verify_checksums = true;
    std::string result;
    Status s = db_->Get(options, handles_[cf], Slice(key), &result);
    if (s.IsNotFound()) {
      result = "NOT_FOUND";
    } else if (!s.ok()) {
      result = s.ToString();
    }
    return result;
  }

  void CompactAll(int cf) {
    ASSERT_OK(db_->CompactRange(handles_[cf], nullptr, nullptr));
  }

  void Compact(int cf, const Slice& start, const Slice& limit) {
    ASSERT_OK(db_->CompactRange(handles_[cf], &start, &limit));
  }

  int NumTableFilesAtLevel(int level, int cf) {
    return GetProperty(cf,
                       "rocksdb.num-files-at-level" + std::to_string(level));
  }

  // Return spread of files per level
  std::string FilesPerLevel(int cf) {
    std::string result;
    int last_non_zero_offset = 0;
    for (int level = 0; level < dbfull()->NumberLevels(handles_[cf]); level++) {
      int f = NumTableFilesAtLevel(level, cf);
      char buf[100];
      snprintf(buf, sizeof(buf), "%s%d", (level ? "," : ""), f);
      result += buf;
      if (f > 0) {
        last_non_zero_offset = result.size();
      }
    }
    result.resize(last_non_zero_offset);
    return result;
  }

  int CountLiveFiles(int cf) {
    std::vector<LiveFileMetaData> metadata;
    db_->GetLiveFilesMetaData(&metadata);
    return static_cast<int>(metadata.size());
  }

  // Do n memtable flushes, each of which produces an sstable
  // covering the range [small,large].
  void MakeTables(int cf, int n, const std::string& small,
                  const std::string& large) {
    for (int i = 0; i < n; i++) {
      ASSERT_OK(Put(cf, small, "begin"));
      ASSERT_OK(Put(cf, large, "end"));
      ASSERT_OK(db_->Flush(FlushOptions(), handles_[cf]));
    }
  }

  int CountLiveLogFiles() {
    int micros_wait_for_log_deletion = 20000;
    env_->SleepForMicroseconds(micros_wait_for_log_deletion);
    int ret = 0;
    VectorLogPtr wal_files;
    Status s;
    // GetSortedWalFiles is a flakey function -- it gets all the wal_dir
    // children files and then later checks for their existance. if some of the
    // log files doesn't exist anymore, it reports an error. it does all of this
    // without DB mutex held, so if a background process deletes the log file
    // while the function is being executed, it returns an error. We retry the
    // function 10 times to avoid the error failing the test
    for (int retries = 0; retries < 10; ++retries) {
      wal_files.clear();
      s = db_->GetSortedWalFiles(wal_files);
      if (s.ok()) {
        break;
      }
    }
    ASSERT_OK(s);
    for (const auto& wal : wal_files) {
      if (wal->Type() == kAliveLogFile) {
        ++ret;
      }
    }
    return ret;
  }

  void AssertNumberOfImmutableMemtables(std::vector<int> num_per_cf) {
    assert(num_per_cf.size() == handles_.size());

    for (size_t i = 0; i < num_per_cf.size(); ++i) {
      ASSERT_EQ(num_per_cf[i],
                GetProperty(i, "rocksdb.num-immutable-mem-table"));
    }
  }

  void CopyFile(const std::string& source, const std::string& destination,
                uint64_t size = 0) {
    const EnvOptions soptions;
    unique_ptr<SequentialFile> srcfile;
    ASSERT_OK(env_->NewSequentialFile(source, &srcfile, soptions));
    unique_ptr<WritableFile> destfile;
    ASSERT_OK(env_->NewWritableFile(destination, &destfile, soptions));

    if (size == 0) {
      // default argument means copy everything
      ASSERT_OK(env_->GetFileSize(source, &size));
    }

    char buffer[4096];
    Slice slice;
    while (size > 0) {
      uint64_t one = std::min(uint64_t(sizeof(buffer)), size);
      ASSERT_OK(srcfile->Read(one, &slice, buffer));
      ASSERT_OK(destfile->Append(slice));
      size -= slice.size();
    }
    ASSERT_OK(destfile->Close());
  }

  std::vector<ColumnFamilyHandle*> handles_;
  std::vector<std::string> names_;
  ColumnFamilyOptions column_family_options_;
  DBOptions db_options_;
  std::string dbname_;
  DB* db_ = nullptr;
  EnvCounter* env_;
  Random rnd_;
};

TEST(ColumnFamilyTest, DontReuseColumnFamilyID) {
  for (int iter = 0; iter < 3; ++iter) {
    Open();
    CreateColumnFamilies({"one", "two", "three"});
    for (size_t i = 0; i < handles_.size(); ++i) {
      auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(handles_[i]);
      ASSERT_EQ(i, cfh->GetID());
    }
    if (iter == 1) {
      Reopen();
    }
    DropColumnFamilies({3});
    Reopen();
    if (iter == 2) {
      // this tests if max_column_family is correctly persisted with
      // WriteSnapshot()
      Reopen();
    }
    CreateColumnFamilies({"three2"});
    // ID 3 that was used for dropped column family "three" should not be reused
    auto cfh3 = reinterpret_cast<ColumnFamilyHandleImpl*>(handles_[3]);
    ASSERT_EQ(4, cfh3->GetID());
    Close();
    Destroy();
  }
}


TEST(ColumnFamilyTest, AddDrop) {
  Open();
  CreateColumnFamilies({"one", "two", "three"});
  ASSERT_EQ("NOT_FOUND", Get(1, "fodor"));
  ASSERT_EQ("NOT_FOUND", Get(2, "fodor"));
  DropColumnFamilies({2});
  ASSERT_EQ("NOT_FOUND", Get(1, "fodor"));
  CreateColumnFamilies({"four"});
  ASSERT_EQ("NOT_FOUND", Get(3, "fodor"));
  ASSERT_OK(Put(1, "fodor", "mirko"));
  ASSERT_EQ("mirko", Get(1, "fodor"));
  ASSERT_EQ("NOT_FOUND", Get(3, "fodor"));
  Close();
  ASSERT_TRUE(TryOpen({"default"}).IsInvalidArgument());
  Open({"default", "one", "three", "four"});
  DropColumnFamilies({1});
  Reopen();
  Close();

  std::vector<std::string> families;
  ASSERT_OK(DB::ListColumnFamilies(db_options_, dbname_, &families));
  sort(families.begin(), families.end());
  ASSERT_TRUE(families ==
              std::vector<std::string>({"default", "four", "three"}));
}

TEST(ColumnFamilyTest, DropTest) {
  // first iteration - dont reopen DB before dropping
  // second iteration - reopen DB before dropping
  for (int iter = 0; iter < 2; ++iter) {
    Open({"default"});
    CreateColumnFamiliesAndReopen({"pikachu"});
    for (int i = 0; i < 100; ++i) {
      ASSERT_OK(Put(1, std::to_string(i), "bar" + std::to_string(i)));
    }
    ASSERT_OK(Flush(1));

    if (iter == 1) {
      Reopen();
    }
    ASSERT_EQ("bar1", Get(1, "1"));

    ASSERT_EQ(CountLiveFiles(1), 1);
    DropColumnFamilies({1});
    // make sure that all files are deleted when we drop the column family
    ASSERT_EQ(CountLiveFiles(1), 0);
    Destroy();
  }
}

TEST(ColumnFamilyTest, WriteBatchFailure) {
  Open();
  CreateColumnFamiliesAndReopen({"one", "two"});
  WriteBatch batch;
  batch.Put(handles_[1], Slice("non-existing"), Slice("column-family"));
  ASSERT_OK(db_->Write(WriteOptions(), &batch));
  DropColumnFamilies({1});
  Status s = db_->Write(WriteOptions(), &batch);
  ASSERT_TRUE(s.IsInvalidArgument());
  Close();
}

TEST(ColumnFamilyTest, ReadWrite) {
  Open();
  CreateColumnFamiliesAndReopen({"one", "two"});
  ASSERT_OK(Put(0, "foo", "v1"));
  ASSERT_OK(Put(0, "bar", "v2"));
  ASSERT_OK(Put(1, "mirko", "v3"));
  ASSERT_OK(Put(0, "foo", "v2"));
  ASSERT_OK(Put(2, "fodor", "v5"));

  for (int iter = 0; iter <= 3; ++iter) {
    ASSERT_EQ("v2", Get(0, "foo"));
    ASSERT_EQ("v2", Get(0, "bar"));
    ASSERT_EQ("v3", Get(1, "mirko"));
    ASSERT_EQ("v5", Get(2, "fodor"));
    ASSERT_EQ("NOT_FOUND", Get(0, "fodor"));
    ASSERT_EQ("NOT_FOUND", Get(1, "fodor"));
    ASSERT_EQ("NOT_FOUND", Get(2, "foo"));
    if (iter <= 1) {
      Reopen();
    }
  }
  Close();
}

TEST(ColumnFamilyTest, IgnoreRecoveredLog) {
  std::string backup_logs = dbname_ + "/backup_logs";

  // delete old files in backup_logs directory
  ASSERT_OK(env_->CreateDirIfMissing(dbname_));
  ASSERT_OK(env_->CreateDirIfMissing(backup_logs));
  std::vector<std::string> old_files;
  env_->GetChildren(backup_logs, &old_files);
  for (auto& file : old_files) {
    if (file != "." && file != "..") {
      env_->DeleteFile(backup_logs + "/" + file);
    }
  }

  column_family_options_.merge_operator =
      MergeOperators::CreateUInt64AddOperator();
  db_options_.wal_dir = dbname_ + "/logs";
  Destroy();
  Open();
  CreateColumnFamilies({"cf1", "cf2"});

  // fill up the DB
  std::string one, two, three;
  PutFixed64(&one, 1);
  PutFixed64(&two, 2);
  PutFixed64(&three, 3);
  ASSERT_OK(Merge(0, "foo", one));
  ASSERT_OK(Merge(1, "mirko", one));
  ASSERT_OK(Merge(0, "foo", one));
  ASSERT_OK(Merge(2, "bla", one));
  ASSERT_OK(Merge(2, "fodor", one));
  ASSERT_OK(Merge(0, "bar", one));
  ASSERT_OK(Merge(2, "bla", one));
  ASSERT_OK(Merge(1, "mirko", two));
  ASSERT_OK(Merge(1, "franjo", one));

  // copy the logs to backup
  std::vector<std::string> logs;
  env_->GetChildren(db_options_.wal_dir, &logs);
  for (auto& log : logs) {
    if (log != ".." && log != ".") {
      CopyFile(db_options_.wal_dir + "/" + log, backup_logs + "/" + log);
    }
  }

  // recover the DB
  Close();

  // 1. check consistency
  // 2. copy the logs from backup back to WAL dir. if the recovery happens
  // again on the same log files, this should lead to incorrect results
  // due to applying merge operator twice
  // 3. check consistency
  for (int iter = 0; iter < 2; ++iter) {
    // assert consistency
    Open({"default", "cf1", "cf2"});
    ASSERT_EQ(two, Get(0, "foo"));
    ASSERT_EQ(one, Get(0, "bar"));
    ASSERT_EQ(three, Get(1, "mirko"));
    ASSERT_EQ(one, Get(1, "franjo"));
    ASSERT_EQ(one, Get(2, "fodor"));
    ASSERT_EQ(two, Get(2, "bla"));
    Close();

    if (iter == 0) {
      // copy the logs from backup back to wal dir
      for (auto& log : logs) {
        if (log != ".." && log != ".") {
          CopyFile(backup_logs + "/" + log, db_options_.wal_dir + "/" + log);
        }
      }
    }
  }
}

TEST(ColumnFamilyTest, FlushTest) {
  Open();
  CreateColumnFamiliesAndReopen({"one", "two"});
  ASSERT_OK(Put(0, "foo", "v1"));
  ASSERT_OK(Put(0, "bar", "v2"));
  ASSERT_OK(Put(1, "mirko", "v3"));
  ASSERT_OK(Put(0, "foo", "v2"));
  ASSERT_OK(Put(2, "fodor", "v5"));
  for (int i = 0; i < 3; ++i) {
    Flush(i);
  }
  Reopen();

  for (int iter = 0; iter <= 2; ++iter) {
    ASSERT_EQ("v2", Get(0, "foo"));
    ASSERT_EQ("v2", Get(0, "bar"));
    ASSERT_EQ("v3", Get(1, "mirko"));
    ASSERT_EQ("v5", Get(2, "fodor"));
    ASSERT_EQ("NOT_FOUND", Get(0, "fodor"));
    ASSERT_EQ("NOT_FOUND", Get(1, "fodor"));
    ASSERT_EQ("NOT_FOUND", Get(2, "foo"));
    if (iter <= 1) {
      Reopen();
    }
  }
  Close();
}

// Makes sure that obsolete log files get deleted
TEST(ColumnFamilyTest, LogDeletionTest) {
  column_family_options_.write_buffer_size = 100000;  // 100KB
  Open();
  CreateColumnFamilies({"one", "two", "three", "four"});
  // Each bracket is one log file. if number is in (), it means
  // we don't need it anymore (it's been flushed)
  // []
  ASSERT_EQ(CountLiveLogFiles(), 0);
  PutRandomData(0, 1, 100);
  // [0]
  PutRandomData(1, 1, 100);
  // [0, 1]
  PutRandomData(1, 1000, 100);
  WaitForFlush(1);
  // [0, (1)] [1]
  ASSERT_EQ(CountLiveLogFiles(), 2);
  PutRandomData(0, 1, 100);
  // [0, (1)] [0, 1]
  ASSERT_EQ(CountLiveLogFiles(), 2);
  PutRandomData(2, 1, 100);
  // [0, (1)] [0, 1, 2]
  PutRandomData(2, 1000, 100);
  WaitForFlush(2);
  // [0, (1)] [0, 1, (2)] [2]
  ASSERT_EQ(CountLiveLogFiles(), 3);
  PutRandomData(2, 1000, 100);
  WaitForFlush(2);
  // [0, (1)] [0, 1, (2)] [(2)] [2]
  ASSERT_EQ(CountLiveLogFiles(), 4);
  PutRandomData(3, 1, 100);
  // [0, (1)] [0, 1, (2)] [(2)] [2, 3]
  PutRandomData(1, 1, 100);
  // [0, (1)] [0, 1, (2)] [(2)] [1, 2, 3]
  ASSERT_EQ(CountLiveLogFiles(), 4);
  PutRandomData(1, 1000, 100);
  WaitForFlush(1);
  // [0, (1)] [0, (1), (2)] [(2)] [(1), 2, 3] [1]
  ASSERT_EQ(CountLiveLogFiles(), 5);
  PutRandomData(0, 1000, 100);
  WaitForFlush(0);
  // [(0), (1)] [(0), (1), (2)] [(2)] [(1), 2, 3] [1, (0)] [0]
  // delete obsolete logs -->
  // [(1), 2, 3] [1, (0)] [0]
  ASSERT_EQ(CountLiveLogFiles(), 3);
  PutRandomData(0, 1000, 100);
  WaitForFlush(0);
  // [(1), 2, 3] [1, (0)], [(0)] [0]
  ASSERT_EQ(CountLiveLogFiles(), 4);
  PutRandomData(1, 1000, 100);
  WaitForFlush(1);
  // [(1), 2, 3] [(1), (0)] [(0)] [0, (1)] [1]
  ASSERT_EQ(CountLiveLogFiles(), 5);
  PutRandomData(2, 1000, 100);
  WaitForFlush(2);
  // [(1), (2), 3] [(1), (0)] [(0)] [0, (1)] [1, (2)], [2]
  ASSERT_EQ(CountLiveLogFiles(), 6);
  PutRandomData(3, 1000, 100);
  WaitForFlush(3);
  // [(1), (2), (3)] [(1), (0)] [(0)] [0, (1)] [1, (2)], [2, (3)] [3]
  // delete obsolete logs -->
  // [0, (1)] [1, (2)], [2, (3)] [3]
  ASSERT_EQ(CountLiveLogFiles(), 4);
  Close();
}

// Makes sure that obsolete log files get deleted
TEST(ColumnFamilyTest, DifferentWriteBufferSizes) {
  Open();
  CreateColumnFamilies({"one", "two", "three"});
  ColumnFamilyOptions default_cf, one, two, three;
  // setup options. all column families have max_write_buffer_number setup to 10
  // "default" -> 100KB memtable, start flushing immediatelly
  // "one" -> 200KB memtable, start flushing with two immutable memtables
  // "two" -> 1MB memtable, start flushing with three immutable memtables
  // "three" -> 90KB memtable, start flushing with four immutable memtables
  default_cf.write_buffer_size = 100000;
  default_cf.max_write_buffer_number = 10;
  default_cf.min_write_buffer_number_to_merge = 1;
  one.write_buffer_size = 200000;
  one.max_write_buffer_number = 10;
  one.min_write_buffer_number_to_merge = 2;
  two.write_buffer_size = 1000000;
  two.max_write_buffer_number = 10;
  two.min_write_buffer_number_to_merge = 3;
  three.write_buffer_size = 90000;
  three.max_write_buffer_number = 10;
  three.min_write_buffer_number_to_merge = 4;

  Reopen({default_cf, one, two, three});

  int micros_wait_for_flush = 10000;
  PutRandomData(0, 100, 1000);
  WaitForFlush(0);
  AssertNumberOfImmutableMemtables({0, 0, 0, 0});
  ASSERT_EQ(CountLiveLogFiles(), 1);
  PutRandomData(1, 200, 1000);
  env_->SleepForMicroseconds(micros_wait_for_flush);
  AssertNumberOfImmutableMemtables({0, 1, 0, 0});
  ASSERT_EQ(CountLiveLogFiles(), 2);
  PutRandomData(2, 1000, 1000);
  env_->SleepForMicroseconds(micros_wait_for_flush);
  AssertNumberOfImmutableMemtables({0, 1, 1, 0});
  ASSERT_EQ(CountLiveLogFiles(), 3);
  PutRandomData(2, 1000, 1000);
  env_->SleepForMicroseconds(micros_wait_for_flush);
  AssertNumberOfImmutableMemtables({0, 1, 2, 0});
  ASSERT_EQ(CountLiveLogFiles(), 4);
  PutRandomData(3, 90, 1000);
  env_->SleepForMicroseconds(micros_wait_for_flush);
  AssertNumberOfImmutableMemtables({0, 1, 2, 1});
  ASSERT_EQ(CountLiveLogFiles(), 5);
  PutRandomData(3, 90, 1000);
  env_->SleepForMicroseconds(micros_wait_for_flush);
  AssertNumberOfImmutableMemtables({0, 1, 2, 2});
  ASSERT_EQ(CountLiveLogFiles(), 6);
  PutRandomData(3, 90, 1000);
  env_->SleepForMicroseconds(micros_wait_for_flush);
  AssertNumberOfImmutableMemtables({0, 1, 2, 3});
  ASSERT_EQ(CountLiveLogFiles(), 7);
  PutRandomData(0, 100, 1000);
  WaitForFlush(0);
  AssertNumberOfImmutableMemtables({0, 1, 2, 3});
  ASSERT_EQ(CountLiveLogFiles(), 8);
  PutRandomData(2, 100, 10000);
  WaitForFlush(2);
  AssertNumberOfImmutableMemtables({0, 1, 0, 3});
  ASSERT_EQ(CountLiveLogFiles(), 9);
  PutRandomData(3, 90, 1000);
  WaitForFlush(3);
  AssertNumberOfImmutableMemtables({0, 1, 0, 0});
  ASSERT_EQ(CountLiveLogFiles(), 10);
  PutRandomData(3, 90, 1000);
  env_->SleepForMicroseconds(micros_wait_for_flush);
  AssertNumberOfImmutableMemtables({0, 1, 0, 1});
  ASSERT_EQ(CountLiveLogFiles(), 11);
  PutRandomData(1, 200, 1000);
  WaitForFlush(1);
  AssertNumberOfImmutableMemtables({0, 0, 0, 1});
  ASSERT_EQ(CountLiveLogFiles(), 5);
  PutRandomData(3, 90*6, 1000);
  WaitForFlush(3);
  AssertNumberOfImmutableMemtables({0, 0, 0, 0});
  ASSERT_EQ(CountLiveLogFiles(), 12);
  PutRandomData(0, 100, 1000);
  WaitForFlush(0);
  AssertNumberOfImmutableMemtables({0, 0, 0, 0});
  ASSERT_EQ(CountLiveLogFiles(), 12);
  PutRandomData(2, 3*100, 10000);
  WaitForFlush(2);
  AssertNumberOfImmutableMemtables({0, 0, 0, 0});
  ASSERT_EQ(CountLiveLogFiles(), 12);
  PutRandomData(1, 2*200, 1000);
  WaitForFlush(1);
  AssertNumberOfImmutableMemtables({0, 0, 0, 0});
  ASSERT_EQ(CountLiveLogFiles(), 7);
  Close();
}

TEST(ColumnFamilyTest, DifferentMergeOperators) {
  Open();
  CreateColumnFamilies({"first", "second"});
  ColumnFamilyOptions default_cf, first, second;
  first.merge_operator = MergeOperators::CreateUInt64AddOperator();
  second.merge_operator = MergeOperators::CreateStringAppendOperator();
  Reopen({default_cf, first, second});

  std::string one, two, three;
  PutFixed64(&one, 1);
  PutFixed64(&two, 2);
  PutFixed64(&three, 3);

  ASSERT_OK(Put(0, "foo", two));
  ASSERT_OK(Put(0, "foo", one));
  ASSERT_TRUE(Merge(0, "foo", two).IsNotSupported());
  ASSERT_EQ(Get(0, "foo"), one);

  ASSERT_OK(Put(1, "foo", two));
  ASSERT_OK(Put(1, "foo", one));
  ASSERT_OK(Merge(1, "foo", two));
  ASSERT_EQ(Get(1, "foo"), three);

  ASSERT_OK(Put(2, "foo", two));
  ASSERT_OK(Put(2, "foo", one));
  ASSERT_OK(Merge(2, "foo", two));
  ASSERT_EQ(Get(2, "foo"), one + "," + two);
  Close();
}

TEST(ColumnFamilyTest, DifferentCompactionStyles) {
  Open();
  CreateColumnFamilies({"one", "two"});
  ColumnFamilyOptions default_cf, one, two;
  db_options_.max_open_files = 20;  // only 10 files in file cache
  db_options_.disableDataSync = true;

  default_cf.compaction_style = kCompactionStyleLevel;
  default_cf.num_levels = 3;
  default_cf.write_buffer_size = 64 << 10;  // 64KB
  default_cf.target_file_size_base = 30 << 10;
  default_cf.filter_policy = nullptr;
  default_cf.no_block_cache = true;
  default_cf.source_compaction_factor = 100;
  default_cf.disable_seek_compaction = false;

  one.compaction_style = kCompactionStyleUniversal;
  // trigger compaction if there are >= 4 files
  one.level0_file_num_compaction_trigger = 4;
  one.write_buffer_size = 100000;

  two.compaction_style = kCompactionStyleLevel;
  two.num_levels = 4;
  two.max_mem_compaction_level = 0;
  two.level0_file_num_compaction_trigger = 3;
  two.write_buffer_size = 100000;

  Reopen({default_cf, one, two});

  // SETUP column family "default" - test read compaction
  ASSERT_EQ("", FilesPerLevel(0));
  PutRandomData(0, 1, 4096);
  ASSERT_OK(Flush(0));
  ASSERT_EQ("0,0,1", FilesPerLevel(0));
  // write 8MB
  PutRandomData(0, 2000, 4096);
  ASSERT_OK(Flush(0));
  // clear levels 0 and 1
  dbfull()->TEST_CompactRange(0, nullptr, nullptr, handles_[0]);
  dbfull()->TEST_CompactRange(1, nullptr, nullptr, handles_[0]);
  ASSERT_EQ(NumTableFilesAtLevel(0, 0), 0);
  ASSERT_EQ(NumTableFilesAtLevel(1, 0), 0);
  // write some new keys into level 0 and 1
  PutRandomData(0, 1024, 512);
  ASSERT_OK(Flush(0));
  WaitForCompaction();
  PutRandomData(0, 10, 512);
  ASSERT_OK(Flush(0));
  // remember number of files in each level
  int l1 = NumTableFilesAtLevel(0, 0);
  int l2 = NumTableFilesAtLevel(1, 0);
  int l3 = NumTableFilesAtLevel(2, 0);
  ASSERT_NE(l1, 0);
  ASSERT_NE(l2, 0);
  ASSERT_NE(l3, 0);

  // SETUP column family "one" -- universal style
  for (int i = 0; i < one.level0_file_num_compaction_trigger - 1; ++i) {
    PutRandomData(1, 11, 10000);
    WaitForFlush(1);
    ASSERT_EQ(std::to_string(i + 1), FilesPerLevel(1));
  }

  // SETUP column family "two" -- level style with 4 levels
  for (int i = 0; i < two.level0_file_num_compaction_trigger - 1; ++i) {
    PutRandomData(2, 15, 10000);
    WaitForFlush(2);
    ASSERT_EQ(std::to_string(i + 1), FilesPerLevel(2));
  }

  // TRIGGER compaction "default"
  // read a bunch of times, trigger read compaction
  for (int i = 0; i < 200000; ++i) {
    Get(0, std::to_string(i));
  }

  // TRIGGER compaction "one"
  PutRandomData(1, 12, 10000);

  // TRIGGER compaction "two"
  PutRandomData(2, 10, 10000);

  // WAIT for compactions
  WaitForCompaction();

  // VERIFY compaction "default"
  // verify that the number of files have decreased
  // in some level, indicating that there was a compaction
  ASSERT_TRUE(NumTableFilesAtLevel(0, 0) < l1 ||
              NumTableFilesAtLevel(1, 0) < l2 ||
              NumTableFilesAtLevel(2, 0) < l3);

  // VERIFY compaction "one"
  ASSERT_EQ("1", FilesPerLevel(1));

  // VERIFY compaction "two"
  ASSERT_EQ("0,1", FilesPerLevel(2));
  CompactAll(2);
  ASSERT_EQ("0,1", FilesPerLevel(2));

  Close();
}

namespace {
std::string IterStatus(Iterator* iter) {
  std::string result;
  if (iter->Valid()) {
    result = iter->key().ToString() + "->" + iter->value().ToString();
  } else {
    result = "(invalid)";
  }
  return result;
}
}  // anonymous namespace

TEST(ColumnFamilyTest, NewIteratorsTest) {
  // iter == 0 -- no tailing
  // iter == 2 -- tailing
  for (int iter = 0; iter < 2; ++iter) {
    Open();
    CreateColumnFamiliesAndReopen({"one", "two"});
    ASSERT_OK(Put(0, "a", "b"));
    ASSERT_OK(Put(1, "b", "a"));
    ASSERT_OK(Put(2, "c", "m"));
    ASSERT_OK(Put(2, "v", "t"));
    std::vector<Iterator*> iterators;
    ReadOptions options;
    options.tailing = (iter == 1);
    ASSERT_OK(db_->NewIterators(options, handles_, &iterators));

    for (auto it : iterators) {
      it->SeekToFirst();
    }
    ASSERT_EQ(IterStatus(iterators[0]), "a->b");
    ASSERT_EQ(IterStatus(iterators[1]), "b->a");
    ASSERT_EQ(IterStatus(iterators[2]), "c->m");

    ASSERT_OK(Put(1, "x", "x"));

    for (auto it : iterators) {
      it->Next();
    }

    ASSERT_EQ(IterStatus(iterators[0]), "(invalid)");
    if (iter == 0) {
      // no tailing
      ASSERT_EQ(IterStatus(iterators[1]), "(invalid)");
    } else {
      // tailing
      ASSERT_EQ(IterStatus(iterators[1]), "x->x");
    }
    ASSERT_EQ(IterStatus(iterators[2]), "v->t");

    for (auto it : iterators) {
      delete it;
    }
    Destroy();
  }
}

TEST(ColumnFamilyTest, ReadOnlyDBTest) {
  Open();
  CreateColumnFamiliesAndReopen({"one", "two", "three", "four"});
  ASSERT_OK(Put(1, "foo", "bla"));
  ASSERT_OK(Put(2, "foo", "blabla"));
  ASSERT_OK(Put(3, "foo", "blablabla"));
  ASSERT_OK(Put(4, "foo", "blablablabla"));

  DropColumnFamilies({2});
  Close();
  // open only a subset of column families
  AssertOpenReadOnly({"default", "one", "four"});
  ASSERT_EQ("NOT_FOUND", Get(0, "foo"));
  ASSERT_EQ("bla", Get(1, "foo"));
  ASSERT_EQ("blablablabla", Get(2, "foo"));

  Close();
  // can't open dropped column family
  Status s = OpenReadOnly({"default", "one", "two"});
  ASSERT_TRUE(!s.ok());

  // Can't open without specifying default column family
  s = OpenReadOnly({"one", "four"});
  ASSERT_TRUE(!s.ok());
}

TEST(ColumnFamilyTest, DontRollEmptyLogs) {
  Open();
  CreateColumnFamiliesAndReopen({"one", "two", "three", "four"});

  for (int i = 0; i < handles_.size(); ++i) {
    PutRandomData(i, 10, 100);
  }
  int num_writable_file_start = env_->GetNumberOfNewWritableFileCalls();
  // this will trigger the flushes
  ASSERT_OK(db_->Write(WriteOptions(), nullptr));

  for (int i = 0; i < 4; ++i) {
    dbfull()->TEST_WaitForFlushMemTable(handles_[i]);
  }
  int total_new_writable_files =
      env_->GetNumberOfNewWritableFileCalls() - num_writable_file_start;
  ASSERT_EQ(total_new_writable_files, handles_.size() + 1);
}

}  // namespace rocksdb

int main(int argc, char** argv) {
  return rocksdb::test::RunAllTests();
}