summaryrefslogtreecommitdiff
path: root/db/recovery_test.cc
blob: 1d9f621c753e599b822f3827005d2d6de1d4e662 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
// Copyright (c) 2014 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 "gtest/gtest.h"
#include "db/db_impl.h"
#include "db/filename.h"
#include "db/version_set.h"
#include "db/write_batch_internal.h"
#include "leveldb/db.h"
#include "leveldb/env.h"
#include "leveldb/write_batch.h"
#include "util/logging.h"
#include "util/testutil.h"

namespace leveldb {

class RecoveryTest : public testing::Test {
 public:
  RecoveryTest() : env_(Env::Default()), db_(nullptr) {
    dbname_ = testing::TempDir() + "recovery_test";
    DestroyDB(dbname_, Options());
    Open();
  }

  ~RecoveryTest() {
    Close();
    DestroyDB(dbname_, Options());
  }

  DBImpl* dbfull() const { return reinterpret_cast<DBImpl*>(db_); }
  Env* env() const { return env_; }

  bool CanAppend() {
    WritableFile* tmp;
    Status s = env_->NewAppendableFile(CurrentFileName(dbname_), &tmp);
    delete tmp;
    if (s.IsNotSupportedError()) {
      return false;
    } else {
      return true;
    }
  }

  void Close() {
    delete db_;
    db_ = nullptr;
  }

  Status OpenWithStatus(Options* options = nullptr) {
    Close();
    Options opts;
    if (options != nullptr) {
      opts = *options;
    } else {
      opts.reuse_logs = true;  // TODO(sanjay): test both ways
      opts.create_if_missing = true;
    }
    if (opts.env == nullptr) {
      opts.env = env_;
    }
    return DB::Open(opts, dbname_, &db_);
  }

  void Open(Options* options = nullptr) {
    ASSERT_LEVELDB_OK(OpenWithStatus(options));
    ASSERT_EQ(1, NumLogs());
  }

  Status Put(const std::string& k, const std::string& v) {
    return db_->Put(WriteOptions(), k, v);
  }

  std::string Get(const std::string& k, const Snapshot* snapshot = nullptr) {
    std::string result;
    Status s = db_->Get(ReadOptions(), k, &result);
    if (s.IsNotFound()) {
      result = "NOT_FOUND";
    } else if (!s.ok()) {
      result = s.ToString();
    }
    return result;
  }

  std::string ManifestFileName() {
    std::string current;
    EXPECT_LEVELDB_OK(
        ReadFileToString(env_, CurrentFileName(dbname_), &current));
    size_t len = current.size();
    if (len > 0 && current[len - 1] == '\n') {
      current.resize(len - 1);
    }
    return dbname_ + "/" + current;
  }

  std::string LogName(uint64_t number) { return LogFileName(dbname_, number); }

  size_t RemoveLogFiles() {
    // Linux allows unlinking open files, but Windows does not.
    // Closing the db allows for file deletion.
    Close();
    std::vector<uint64_t> logs = GetFiles(kLogFile);
    for (size_t i = 0; i < logs.size(); i++) {
      EXPECT_LEVELDB_OK(env_->RemoveFile(LogName(logs[i]))) << LogName(logs[i]);
    }
    return logs.size();
  }

  void RemoveManifestFile() {
    ASSERT_LEVELDB_OK(env_->RemoveFile(ManifestFileName()));
  }

  uint64_t FirstLogFile() { return GetFiles(kLogFile)[0]; }

  std::vector<uint64_t> GetFiles(FileType t) {
    std::vector<std::string> filenames;
    EXPECT_LEVELDB_OK(env_->GetChildren(dbname_, &filenames));
    std::vector<uint64_t> result;
    for (size_t i = 0; i < filenames.size(); i++) {
      uint64_t number;
      FileType type;
      if (ParseFileName(filenames[i], &number, &type) && type == t) {
        result.push_back(number);
      }
    }
    return result;
  }

  int NumLogs() { return GetFiles(kLogFile).size(); }

  int NumTables() { return GetFiles(kTableFile).size(); }

  uint64_t FileSize(const std::string& fname) {
    uint64_t result;
    EXPECT_LEVELDB_OK(env_->GetFileSize(fname, &result)) << fname;
    return result;
  }

  void CompactMemTable() { dbfull()->TEST_CompactMemTable(); }

  // Directly construct a log file that sets key to val.
  void MakeLogFile(uint64_t lognum, SequenceNumber seq, Slice key, Slice val) {
    std::string fname = LogFileName(dbname_, lognum);
    WritableFile* file;
    ASSERT_LEVELDB_OK(env_->NewWritableFile(fname, &file));
    log::Writer writer(file);
    WriteBatch batch;
    batch.Put(key, val);
    WriteBatchInternal::SetSequence(&batch, seq);
    ASSERT_LEVELDB_OK(writer.AddRecord(WriteBatchInternal::Contents(&batch)));
    ASSERT_LEVELDB_OK(file->Flush());
    delete file;
  }

 private:
  std::string dbname_;
  Env* env_;
  DB* db_;
};

TEST_F(RecoveryTest, ManifestReused) {
  if (!CanAppend()) {
    std::fprintf(stderr,
                 "skipping test because env does not support appending\n");
    return;
  }
  ASSERT_LEVELDB_OK(Put("foo", "bar"));
  Close();
  std::string old_manifest = ManifestFileName();
  Open();
  ASSERT_EQ(old_manifest, ManifestFileName());
  ASSERT_EQ("bar", Get("foo"));
  Open();
  ASSERT_EQ(old_manifest, ManifestFileName());
  ASSERT_EQ("bar", Get("foo"));
}

TEST_F(RecoveryTest, LargeManifestCompacted) {
  if (!CanAppend()) {
    std::fprintf(stderr,
                 "skipping test because env does not support appending\n");
    return;
  }
  ASSERT_LEVELDB_OK(Put("foo", "bar"));
  Close();
  std::string old_manifest = ManifestFileName();

  // Pad with zeroes to make manifest file very big.
  {
    uint64_t len = FileSize(old_manifest);
    WritableFile* file;
    ASSERT_LEVELDB_OK(env()->NewAppendableFile(old_manifest, &file));
    std::string zeroes(3 * 1048576 - static_cast<size_t>(len), 0);
    ASSERT_LEVELDB_OK(file->Append(zeroes));
    ASSERT_LEVELDB_OK(file->Flush());
    delete file;
  }

  Open();
  std::string new_manifest = ManifestFileName();
  ASSERT_NE(old_manifest, new_manifest);
  ASSERT_GT(10000, FileSize(new_manifest));
  ASSERT_EQ("bar", Get("foo"));

  Open();
  ASSERT_EQ(new_manifest, ManifestFileName());
  ASSERT_EQ("bar", Get("foo"));
}

TEST_F(RecoveryTest, NoLogFiles) {
  ASSERT_LEVELDB_OK(Put("foo", "bar"));
  ASSERT_EQ(1, RemoveLogFiles());
  Open();
  ASSERT_EQ("NOT_FOUND", Get("foo"));
  Open();
  ASSERT_EQ("NOT_FOUND", Get("foo"));
}

TEST_F(RecoveryTest, LogFileReuse) {
  if (!CanAppend()) {
    std::fprintf(stderr,
                 "skipping test because env does not support appending\n");
    return;
  }
  for (int i = 0; i < 2; i++) {
    ASSERT_LEVELDB_OK(Put("foo", "bar"));
    if (i == 0) {
      // Compact to ensure current log is empty
      CompactMemTable();
    }
    Close();
    ASSERT_EQ(1, NumLogs());
    uint64_t number = FirstLogFile();
    if (i == 0) {
      ASSERT_EQ(0, FileSize(LogName(number)));
    } else {
      ASSERT_LT(0, FileSize(LogName(number)));
    }
    Open();
    ASSERT_EQ(1, NumLogs());
    ASSERT_EQ(number, FirstLogFile()) << "did not reuse log file";
    ASSERT_EQ("bar", Get("foo"));
    Open();
    ASSERT_EQ(1, NumLogs());
    ASSERT_EQ(number, FirstLogFile()) << "did not reuse log file";
    ASSERT_EQ("bar", Get("foo"));
  }
}

TEST_F(RecoveryTest, MultipleMemTables) {
  // Make a large log.
  const int kNum = 1000;
  for (int i = 0; i < kNum; i++) {
    char buf[100];
    std::snprintf(buf, sizeof(buf), "%050d", i);
    ASSERT_LEVELDB_OK(Put(buf, buf));
  }
  ASSERT_EQ(0, NumTables());
  Close();
  ASSERT_EQ(0, NumTables());
  ASSERT_EQ(1, NumLogs());
  uint64_t old_log_file = FirstLogFile();

  // Force creation of multiple memtables by reducing the write buffer size.
  Options opt;
  opt.reuse_logs = true;
  opt.write_buffer_size = (kNum * 100) / 2;
  Open(&opt);
  ASSERT_LE(2, NumTables());
  ASSERT_EQ(1, NumLogs());
  ASSERT_NE(old_log_file, FirstLogFile()) << "must not reuse log";
  for (int i = 0; i < kNum; i++) {
    char buf[100];
    std::snprintf(buf, sizeof(buf), "%050d", i);
    ASSERT_EQ(buf, Get(buf));
  }
}

TEST_F(RecoveryTest, MultipleLogFiles) {
  ASSERT_LEVELDB_OK(Put("foo", "bar"));
  Close();
  ASSERT_EQ(1, NumLogs());

  // Make a bunch of uncompacted log files.
  uint64_t old_log = FirstLogFile();
  MakeLogFile(old_log + 1, 1000, "hello", "world");
  MakeLogFile(old_log + 2, 1001, "hi", "there");
  MakeLogFile(old_log + 3, 1002, "foo", "bar2");

  // Recover and check that all log files were processed.
  Open();
  ASSERT_LE(1, NumTables());
  ASSERT_EQ(1, NumLogs());
  uint64_t new_log = FirstLogFile();
  ASSERT_LE(old_log + 3, new_log);
  ASSERT_EQ("bar2", Get("foo"));
  ASSERT_EQ("world", Get("hello"));
  ASSERT_EQ("there", Get("hi"));

  // Test that previous recovery produced recoverable state.
  Open();
  ASSERT_LE(1, NumTables());
  ASSERT_EQ(1, NumLogs());
  if (CanAppend()) {
    ASSERT_EQ(new_log, FirstLogFile());
  }
  ASSERT_EQ("bar2", Get("foo"));
  ASSERT_EQ("world", Get("hello"));
  ASSERT_EQ("there", Get("hi"));

  // Check that introducing an older log file does not cause it to be re-read.
  Close();
  MakeLogFile(old_log + 1, 2000, "hello", "stale write");
  Open();
  ASSERT_LE(1, NumTables());
  ASSERT_EQ(1, NumLogs());
  if (CanAppend()) {
    ASSERT_EQ(new_log, FirstLogFile());
  }
  ASSERT_EQ("bar2", Get("foo"));
  ASSERT_EQ("world", Get("hello"));
  ASSERT_EQ("there", Get("hi"));
}

TEST_F(RecoveryTest, ManifestMissing) {
  ASSERT_LEVELDB_OK(Put("foo", "bar"));
  Close();
  RemoveManifestFile();

  Status status = OpenWithStatus();
  ASSERT_TRUE(status.IsCorruption());
}

}  // namespace leveldb