xref: /aosp_15_r20/external/leveldb/benchmarks/db_bench_sqlite3.cc (revision 9507f98c5f32dee4b5f9e4a38cd499f3ff5c4490)
1 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file. See the AUTHORS file for names of contributors.
4 
5 #include <sqlite3.h>
6 
7 #include <cstdio>
8 #include <cstdlib>
9 
10 #include "util/histogram.h"
11 #include "util/random.h"
12 #include "util/testutil.h"
13 
14 // Comma-separated list of operations to run in the specified order
15 //   Actual benchmarks:
16 //
17 //   fillseq       -- write N values in sequential key order in async mode
18 //   fillseqsync   -- write N/100 values in sequential key order in sync mode
19 //   fillseqbatch  -- batch write N values in sequential key order in async mode
20 //   fillrandom    -- write N values in random key order in async mode
21 //   fillrandsync  -- write N/100 values in random key order in sync mode
22 //   fillrandbatch -- batch write N values in sequential key order in async mode
23 //   overwrite     -- overwrite N values in random key order in async mode
24 //   fillrand100K  -- write N/1000 100K values in random order in async mode
25 //   fillseq100K   -- write N/1000 100K values in sequential order in async mode
26 //   readseq       -- read N times sequentially
27 //   readrandom    -- read N times in random order
28 //   readrand100K  -- read N/1000 100K values in sequential order in async mode
29 static const char* FLAGS_benchmarks =
30     "fillseq,"
31     "fillseqsync,"
32     "fillseqbatch,"
33     "fillrandom,"
34     "fillrandsync,"
35     "fillrandbatch,"
36     "overwrite,"
37     "overwritebatch,"
38     "readrandom,"
39     "readseq,"
40     "fillrand100K,"
41     "fillseq100K,"
42     "readseq,"
43     "readrand100K,";
44 
45 // Number of key/values to place in database
46 static int FLAGS_num = 1000000;
47 
48 // Number of read operations to do.  If negative, do FLAGS_num reads.
49 static int FLAGS_reads = -1;
50 
51 // Size of each value
52 static int FLAGS_value_size = 100;
53 
54 // Print histogram of operation timings
55 static bool FLAGS_histogram = false;
56 
57 // Arrange to generate values that shrink to this fraction of
58 // their original size after compression
59 static double FLAGS_compression_ratio = 0.5;
60 
61 // Page size. Default 1 KB.
62 static int FLAGS_page_size = 1024;
63 
64 // Number of pages.
65 // Default cache size = FLAGS_page_size * FLAGS_num_pages = 4 MB.
66 static int FLAGS_num_pages = 4096;
67 
68 // If true, do not destroy the existing database.  If you set this
69 // flag and also specify a benchmark that wants a fresh database, that
70 // benchmark will fail.
71 static bool FLAGS_use_existing_db = false;
72 
73 // If true, the SQLite table has ROWIDs.
74 static bool FLAGS_use_rowids = false;
75 
76 // If true, we allow batch writes to occur
77 static bool FLAGS_transaction = true;
78 
79 // If true, we enable Write-Ahead Logging
80 static bool FLAGS_WAL_enabled = true;
81 
82 // Use the db with the following name.
83 static const char* FLAGS_db = nullptr;
84 
ExecErrorCheck(int status,char * err_msg)85 inline static void ExecErrorCheck(int status, char* err_msg) {
86   if (status != SQLITE_OK) {
87     std::fprintf(stderr, "SQL error: %s\n", err_msg);
88     sqlite3_free(err_msg);
89     std::exit(1);
90   }
91 }
92 
StepErrorCheck(int status)93 inline static void StepErrorCheck(int status) {
94   if (status != SQLITE_DONE) {
95     std::fprintf(stderr, "SQL step error: status = %d\n", status);
96     std::exit(1);
97   }
98 }
99 
ErrorCheck(int status)100 inline static void ErrorCheck(int status) {
101   if (status != SQLITE_OK) {
102     std::fprintf(stderr, "sqlite3 error: status = %d\n", status);
103     std::exit(1);
104   }
105 }
106 
WalCheckpoint(sqlite3 * db_)107 inline static void WalCheckpoint(sqlite3* db_) {
108   // Flush all writes to disk
109   if (FLAGS_WAL_enabled) {
110     sqlite3_wal_checkpoint_v2(db_, nullptr, SQLITE_CHECKPOINT_FULL, nullptr,
111                               nullptr);
112   }
113 }
114 
115 namespace leveldb {
116 
117 // Helper for quickly generating random data.
118 namespace {
119 class RandomGenerator {
120  private:
121   std::string data_;
122   int pos_;
123 
124  public:
RandomGenerator()125   RandomGenerator() {
126     // We use a limited amount of data over and over again and ensure
127     // that it is larger than the compression window (32KB), and also
128     // large enough to serve all typical value sizes we want to write.
129     Random rnd(301);
130     std::string piece;
131     while (data_.size() < 1048576) {
132       // Add a short fragment that is as compressible as specified
133       // by FLAGS_compression_ratio.
134       test::CompressibleString(&rnd, FLAGS_compression_ratio, 100, &piece);
135       data_.append(piece);
136     }
137     pos_ = 0;
138   }
139 
Generate(int len)140   Slice Generate(int len) {
141     if (pos_ + len > data_.size()) {
142       pos_ = 0;
143       assert(len < data_.size());
144     }
145     pos_ += len;
146     return Slice(data_.data() + pos_ - len, len);
147   }
148 };
149 
TrimSpace(Slice s)150 static Slice TrimSpace(Slice s) {
151   int start = 0;
152   while (start < s.size() && isspace(s[start])) {
153     start++;
154   }
155   int limit = s.size();
156   while (limit > start && isspace(s[limit - 1])) {
157     limit--;
158   }
159   return Slice(s.data() + start, limit - start);
160 }
161 
162 }  // namespace
163 
164 class Benchmark {
165  private:
166   sqlite3* db_;
167   int db_num_;
168   int num_;
169   int reads_;
170   double start_;
171   double last_op_finish_;
172   int64_t bytes_;
173   std::string message_;
174   Histogram hist_;
175   RandomGenerator gen_;
176   Random rand_;
177 
178   // State kept for progress messages
179   int done_;
180   int next_report_;  // When to report next
181 
PrintHeader()182   void PrintHeader() {
183     const int kKeySize = 16;
184     PrintEnvironment();
185     std::fprintf(stdout, "Keys:       %d bytes each\n", kKeySize);
186     std::fprintf(stdout, "Values:     %d bytes each\n", FLAGS_value_size);
187     std::fprintf(stdout, "Entries:    %d\n", num_);
188     std::fprintf(stdout, "RawSize:    %.1f MB (estimated)\n",
189                  ((static_cast<int64_t>(kKeySize + FLAGS_value_size) * num_) /
190                   1048576.0));
191     PrintWarnings();
192     std::fprintf(stdout, "------------------------------------------------\n");
193   }
194 
PrintWarnings()195   void PrintWarnings() {
196 #if defined(__GNUC__) && !defined(__OPTIMIZE__)
197     std::fprintf(
198         stdout,
199         "WARNING: Optimization is disabled: benchmarks unnecessarily slow\n");
200 #endif
201 #ifndef NDEBUG
202     std::fprintf(
203         stdout,
204         "WARNING: Assertions are enabled; benchmarks unnecessarily slow\n");
205 #endif
206   }
207 
PrintEnvironment()208   void PrintEnvironment() {
209     std::fprintf(stderr, "SQLite:     version %s\n", SQLITE_VERSION);
210 
211 #if defined(__linux)
212     time_t now = time(nullptr);
213     std::fprintf(stderr, "Date:       %s",
214                  ctime(&now));  // ctime() adds newline
215 
216     FILE* cpuinfo = std::fopen("/proc/cpuinfo", "r");
217     if (cpuinfo != nullptr) {
218       char line[1000];
219       int num_cpus = 0;
220       std::string cpu_type;
221       std::string cache_size;
222       while (fgets(line, sizeof(line), cpuinfo) != nullptr) {
223         const char* sep = strchr(line, ':');
224         if (sep == nullptr) {
225           continue;
226         }
227         Slice key = TrimSpace(Slice(line, sep - 1 - line));
228         Slice val = TrimSpace(Slice(sep + 1));
229         if (key == "model name") {
230           ++num_cpus;
231           cpu_type = val.ToString();
232         } else if (key == "cache size") {
233           cache_size = val.ToString();
234         }
235       }
236       std::fclose(cpuinfo);
237       std::fprintf(stderr, "CPU:        %d * %s\n", num_cpus, cpu_type.c_str());
238       std::fprintf(stderr, "CPUCache:   %s\n", cache_size.c_str());
239     }
240 #endif
241   }
242 
Start()243   void Start() {
244     start_ = Env::Default()->NowMicros() * 1e-6;
245     bytes_ = 0;
246     message_.clear();
247     last_op_finish_ = start_;
248     hist_.Clear();
249     done_ = 0;
250     next_report_ = 100;
251   }
252 
FinishedSingleOp()253   void FinishedSingleOp() {
254     if (FLAGS_histogram) {
255       double now = Env::Default()->NowMicros() * 1e-6;
256       double micros = (now - last_op_finish_) * 1e6;
257       hist_.Add(micros);
258       if (micros > 20000) {
259         std::fprintf(stderr, "long op: %.1f micros%30s\r", micros, "");
260         std::fflush(stderr);
261       }
262       last_op_finish_ = now;
263     }
264 
265     done_++;
266     if (done_ >= next_report_) {
267       if (next_report_ < 1000)
268         next_report_ += 100;
269       else if (next_report_ < 5000)
270         next_report_ += 500;
271       else if (next_report_ < 10000)
272         next_report_ += 1000;
273       else if (next_report_ < 50000)
274         next_report_ += 5000;
275       else if (next_report_ < 100000)
276         next_report_ += 10000;
277       else if (next_report_ < 500000)
278         next_report_ += 50000;
279       else
280         next_report_ += 100000;
281       std::fprintf(stderr, "... finished %d ops%30s\r", done_, "");
282       std::fflush(stderr);
283     }
284   }
285 
Stop(const Slice & name)286   void Stop(const Slice& name) {
287     double finish = Env::Default()->NowMicros() * 1e-6;
288 
289     // Pretend at least one op was done in case we are running a benchmark
290     // that does not call FinishedSingleOp().
291     if (done_ < 1) done_ = 1;
292 
293     if (bytes_ > 0) {
294       char rate[100];
295       std::snprintf(rate, sizeof(rate), "%6.1f MB/s",
296                     (bytes_ / 1048576.0) / (finish - start_));
297       if (!message_.empty()) {
298         message_ = std::string(rate) + " " + message_;
299       } else {
300         message_ = rate;
301       }
302     }
303 
304     std::fprintf(stdout, "%-12s : %11.3f micros/op;%s%s\n",
305                  name.ToString().c_str(), (finish - start_) * 1e6 / done_,
306                  (message_.empty() ? "" : " "), message_.c_str());
307     if (FLAGS_histogram) {
308       std::fprintf(stdout, "Microseconds per op:\n%s\n",
309                    hist_.ToString().c_str());
310     }
311     std::fflush(stdout);
312   }
313 
314  public:
315   enum Order { SEQUENTIAL, RANDOM };
316   enum DBState { FRESH, EXISTING };
317 
Benchmark()318   Benchmark()
319       : db_(nullptr),
320         db_num_(0),
321         num_(FLAGS_num),
322         reads_(FLAGS_reads < 0 ? FLAGS_num : FLAGS_reads),
323         bytes_(0),
324         rand_(301) {
325     std::vector<std::string> files;
326     std::string test_dir;
327     Env::Default()->GetTestDirectory(&test_dir);
328     Env::Default()->GetChildren(test_dir, &files);
329     if (!FLAGS_use_existing_db) {
330       for (int i = 0; i < files.size(); i++) {
331         if (Slice(files[i]).starts_with("dbbench_sqlite3")) {
332           std::string file_name(test_dir);
333           file_name += "/";
334           file_name += files[i];
335           Env::Default()->RemoveFile(file_name.c_str());
336         }
337       }
338     }
339   }
340 
~Benchmark()341   ~Benchmark() {
342     int status = sqlite3_close(db_);
343     ErrorCheck(status);
344   }
345 
Run()346   void Run() {
347     PrintHeader();
348     Open();
349 
350     const char* benchmarks = FLAGS_benchmarks;
351     while (benchmarks != nullptr) {
352       const char* sep = strchr(benchmarks, ',');
353       Slice name;
354       if (sep == nullptr) {
355         name = benchmarks;
356         benchmarks = nullptr;
357       } else {
358         name = Slice(benchmarks, sep - benchmarks);
359         benchmarks = sep + 1;
360       }
361 
362       bytes_ = 0;
363       Start();
364 
365       bool known = true;
366       bool write_sync = false;
367       if (name == Slice("fillseq")) {
368         Write(write_sync, SEQUENTIAL, FRESH, num_, FLAGS_value_size, 1);
369         WalCheckpoint(db_);
370       } else if (name == Slice("fillseqbatch")) {
371         Write(write_sync, SEQUENTIAL, FRESH, num_, FLAGS_value_size, 1000);
372         WalCheckpoint(db_);
373       } else if (name == Slice("fillrandom")) {
374         Write(write_sync, RANDOM, FRESH, num_, FLAGS_value_size, 1);
375         WalCheckpoint(db_);
376       } else if (name == Slice("fillrandbatch")) {
377         Write(write_sync, RANDOM, FRESH, num_, FLAGS_value_size, 1000);
378         WalCheckpoint(db_);
379       } else if (name == Slice("overwrite")) {
380         Write(write_sync, RANDOM, EXISTING, num_, FLAGS_value_size, 1);
381         WalCheckpoint(db_);
382       } else if (name == Slice("overwritebatch")) {
383         Write(write_sync, RANDOM, EXISTING, num_, FLAGS_value_size, 1000);
384         WalCheckpoint(db_);
385       } else if (name == Slice("fillrandsync")) {
386         write_sync = true;
387         Write(write_sync, RANDOM, FRESH, num_ / 100, FLAGS_value_size, 1);
388         WalCheckpoint(db_);
389       } else if (name == Slice("fillseqsync")) {
390         write_sync = true;
391         Write(write_sync, SEQUENTIAL, FRESH, num_ / 100, FLAGS_value_size, 1);
392         WalCheckpoint(db_);
393       } else if (name == Slice("fillrand100K")) {
394         Write(write_sync, RANDOM, FRESH, num_ / 1000, 100 * 1000, 1);
395         WalCheckpoint(db_);
396       } else if (name == Slice("fillseq100K")) {
397         Write(write_sync, SEQUENTIAL, FRESH, num_ / 1000, 100 * 1000, 1);
398         WalCheckpoint(db_);
399       } else if (name == Slice("readseq")) {
400         ReadSequential();
401       } else if (name == Slice("readrandom")) {
402         Read(RANDOM, 1);
403       } else if (name == Slice("readrand100K")) {
404         int n = reads_;
405         reads_ /= 1000;
406         Read(RANDOM, 1);
407         reads_ = n;
408       } else {
409         known = false;
410         if (name != Slice()) {  // No error message for empty name
411           std::fprintf(stderr, "unknown benchmark '%s'\n",
412                        name.ToString().c_str());
413         }
414       }
415       if (known) {
416         Stop(name);
417       }
418     }
419   }
420 
Open()421   void Open() {
422     assert(db_ == nullptr);
423 
424     int status;
425     char file_name[100];
426     char* err_msg = nullptr;
427     db_num_++;
428 
429     // Open database
430     std::string tmp_dir;
431     Env::Default()->GetTestDirectory(&tmp_dir);
432     std::snprintf(file_name, sizeof(file_name), "%s/dbbench_sqlite3-%d.db",
433                   tmp_dir.c_str(), db_num_);
434     status = sqlite3_open(file_name, &db_);
435     if (status) {
436       std::fprintf(stderr, "open error: %s\n", sqlite3_errmsg(db_));
437       std::exit(1);
438     }
439 
440     // Change SQLite cache size
441     char cache_size[100];
442     std::snprintf(cache_size, sizeof(cache_size), "PRAGMA cache_size = %d",
443                   FLAGS_num_pages);
444     status = sqlite3_exec(db_, cache_size, nullptr, nullptr, &err_msg);
445     ExecErrorCheck(status, err_msg);
446 
447     // FLAGS_page_size is defaulted to 1024
448     if (FLAGS_page_size != 1024) {
449       char page_size[100];
450       std::snprintf(page_size, sizeof(page_size), "PRAGMA page_size = %d",
451                     FLAGS_page_size);
452       status = sqlite3_exec(db_, page_size, nullptr, nullptr, &err_msg);
453       ExecErrorCheck(status, err_msg);
454     }
455 
456     // Change journal mode to WAL if WAL enabled flag is on
457     if (FLAGS_WAL_enabled) {
458       std::string WAL_stmt = "PRAGMA journal_mode = WAL";
459 
460       // LevelDB's default cache size is a combined 4 MB
461       std::string WAL_checkpoint = "PRAGMA wal_autocheckpoint = 4096";
462       status = sqlite3_exec(db_, WAL_stmt.c_str(), nullptr, nullptr, &err_msg);
463       ExecErrorCheck(status, err_msg);
464       status =
465           sqlite3_exec(db_, WAL_checkpoint.c_str(), nullptr, nullptr, &err_msg);
466       ExecErrorCheck(status, err_msg);
467     }
468 
469     // Change locking mode to exclusive and create tables/index for database
470     std::string locking_stmt = "PRAGMA locking_mode = EXCLUSIVE";
471     std::string create_stmt =
472         "CREATE TABLE test (key blob, value blob, PRIMARY KEY(key))";
473     if (!FLAGS_use_rowids) create_stmt += " WITHOUT ROWID";
474     std::string stmt_array[] = {locking_stmt, create_stmt};
475     int stmt_array_length = sizeof(stmt_array) / sizeof(std::string);
476     for (int i = 0; i < stmt_array_length; i++) {
477       status =
478           sqlite3_exec(db_, stmt_array[i].c_str(), nullptr, nullptr, &err_msg);
479       ExecErrorCheck(status, err_msg);
480     }
481   }
482 
Write(bool write_sync,Order order,DBState state,int num_entries,int value_size,int entries_per_batch)483   void Write(bool write_sync, Order order, DBState state, int num_entries,
484              int value_size, int entries_per_batch) {
485     // Create new database if state == FRESH
486     if (state == FRESH) {
487       if (FLAGS_use_existing_db) {
488         message_ = "skipping (--use_existing_db is true)";
489         return;
490       }
491       sqlite3_close(db_);
492       db_ = nullptr;
493       Open();
494       Start();
495     }
496 
497     if (num_entries != num_) {
498       char msg[100];
499       std::snprintf(msg, sizeof(msg), "(%d ops)", num_entries);
500       message_ = msg;
501     }
502 
503     char* err_msg = nullptr;
504     int status;
505 
506     sqlite3_stmt *replace_stmt, *begin_trans_stmt, *end_trans_stmt;
507     std::string replace_str = "REPLACE INTO test (key, value) VALUES (?, ?)";
508     std::string begin_trans_str = "BEGIN TRANSACTION;";
509     std::string end_trans_str = "END TRANSACTION;";
510 
511     // Check for synchronous flag in options
512     std::string sync_stmt =
513         (write_sync) ? "PRAGMA synchronous = FULL" : "PRAGMA synchronous = OFF";
514     status = sqlite3_exec(db_, sync_stmt.c_str(), nullptr, nullptr, &err_msg);
515     ExecErrorCheck(status, err_msg);
516 
517     // Preparing sqlite3 statements
518     status = sqlite3_prepare_v2(db_, replace_str.c_str(), -1, &replace_stmt,
519                                 nullptr);
520     ErrorCheck(status);
521     status = sqlite3_prepare_v2(db_, begin_trans_str.c_str(), -1,
522                                 &begin_trans_stmt, nullptr);
523     ErrorCheck(status);
524     status = sqlite3_prepare_v2(db_, end_trans_str.c_str(), -1, &end_trans_stmt,
525                                 nullptr);
526     ErrorCheck(status);
527 
528     bool transaction = (entries_per_batch > 1);
529     for (int i = 0; i < num_entries; i += entries_per_batch) {
530       // Begin write transaction
531       if (FLAGS_transaction && transaction) {
532         status = sqlite3_step(begin_trans_stmt);
533         StepErrorCheck(status);
534         status = sqlite3_reset(begin_trans_stmt);
535         ErrorCheck(status);
536       }
537 
538       // Create and execute SQL statements
539       for (int j = 0; j < entries_per_batch; j++) {
540         const char* value = gen_.Generate(value_size).data();
541 
542         // Create values for key-value pair
543         const int k =
544             (order == SEQUENTIAL) ? i + j : (rand_.Next() % num_entries);
545         char key[100];
546         std::snprintf(key, sizeof(key), "%016d", k);
547 
548         // Bind KV values into replace_stmt
549         status = sqlite3_bind_blob(replace_stmt, 1, key, 16, SQLITE_STATIC);
550         ErrorCheck(status);
551         status = sqlite3_bind_blob(replace_stmt, 2, value, value_size,
552                                    SQLITE_STATIC);
553         ErrorCheck(status);
554 
555         // Execute replace_stmt
556         bytes_ += value_size + strlen(key);
557         status = sqlite3_step(replace_stmt);
558         StepErrorCheck(status);
559 
560         // Reset SQLite statement for another use
561         status = sqlite3_clear_bindings(replace_stmt);
562         ErrorCheck(status);
563         status = sqlite3_reset(replace_stmt);
564         ErrorCheck(status);
565 
566         FinishedSingleOp();
567       }
568 
569       // End write transaction
570       if (FLAGS_transaction && transaction) {
571         status = sqlite3_step(end_trans_stmt);
572         StepErrorCheck(status);
573         status = sqlite3_reset(end_trans_stmt);
574         ErrorCheck(status);
575       }
576     }
577 
578     status = sqlite3_finalize(replace_stmt);
579     ErrorCheck(status);
580     status = sqlite3_finalize(begin_trans_stmt);
581     ErrorCheck(status);
582     status = sqlite3_finalize(end_trans_stmt);
583     ErrorCheck(status);
584   }
585 
Read(Order order,int entries_per_batch)586   void Read(Order order, int entries_per_batch) {
587     int status;
588     sqlite3_stmt *read_stmt, *begin_trans_stmt, *end_trans_stmt;
589 
590     std::string read_str = "SELECT * FROM test WHERE key = ?";
591     std::string begin_trans_str = "BEGIN TRANSACTION;";
592     std::string end_trans_str = "END TRANSACTION;";
593 
594     // Preparing sqlite3 statements
595     status = sqlite3_prepare_v2(db_, begin_trans_str.c_str(), -1,
596                                 &begin_trans_stmt, nullptr);
597     ErrorCheck(status);
598     status = sqlite3_prepare_v2(db_, end_trans_str.c_str(), -1, &end_trans_stmt,
599                                 nullptr);
600     ErrorCheck(status);
601     status = sqlite3_prepare_v2(db_, read_str.c_str(), -1, &read_stmt, nullptr);
602     ErrorCheck(status);
603 
604     bool transaction = (entries_per_batch > 1);
605     for (int i = 0; i < reads_; i += entries_per_batch) {
606       // Begin read transaction
607       if (FLAGS_transaction && transaction) {
608         status = sqlite3_step(begin_trans_stmt);
609         StepErrorCheck(status);
610         status = sqlite3_reset(begin_trans_stmt);
611         ErrorCheck(status);
612       }
613 
614       // Create and execute SQL statements
615       for (int j = 0; j < entries_per_batch; j++) {
616         // Create key value
617         char key[100];
618         int k = (order == SEQUENTIAL) ? i + j : (rand_.Next() % reads_);
619         std::snprintf(key, sizeof(key), "%016d", k);
620 
621         // Bind key value into read_stmt
622         status = sqlite3_bind_blob(read_stmt, 1, key, 16, SQLITE_STATIC);
623         ErrorCheck(status);
624 
625         // Execute read statement
626         while ((status = sqlite3_step(read_stmt)) == SQLITE_ROW) {
627         }
628         StepErrorCheck(status);
629 
630         // Reset SQLite statement for another use
631         status = sqlite3_clear_bindings(read_stmt);
632         ErrorCheck(status);
633         status = sqlite3_reset(read_stmt);
634         ErrorCheck(status);
635         FinishedSingleOp();
636       }
637 
638       // End read transaction
639       if (FLAGS_transaction && transaction) {
640         status = sqlite3_step(end_trans_stmt);
641         StepErrorCheck(status);
642         status = sqlite3_reset(end_trans_stmt);
643         ErrorCheck(status);
644       }
645     }
646 
647     status = sqlite3_finalize(read_stmt);
648     ErrorCheck(status);
649     status = sqlite3_finalize(begin_trans_stmt);
650     ErrorCheck(status);
651     status = sqlite3_finalize(end_trans_stmt);
652     ErrorCheck(status);
653   }
654 
ReadSequential()655   void ReadSequential() {
656     int status;
657     sqlite3_stmt* pStmt;
658     std::string read_str = "SELECT * FROM test ORDER BY key";
659 
660     status = sqlite3_prepare_v2(db_, read_str.c_str(), -1, &pStmt, nullptr);
661     ErrorCheck(status);
662     for (int i = 0; i < reads_ && SQLITE_ROW == sqlite3_step(pStmt); i++) {
663       bytes_ += sqlite3_column_bytes(pStmt, 1) + sqlite3_column_bytes(pStmt, 2);
664       FinishedSingleOp();
665     }
666 
667     status = sqlite3_finalize(pStmt);
668     ErrorCheck(status);
669   }
670 };
671 
672 }  // namespace leveldb
673 
main(int argc,char ** argv)674 int main(int argc, char** argv) {
675   std::string default_db_path;
676   for (int i = 1; i < argc; i++) {
677     double d;
678     int n;
679     char junk;
680     if (leveldb::Slice(argv[i]).starts_with("--benchmarks=")) {
681       FLAGS_benchmarks = argv[i] + strlen("--benchmarks=");
682     } else if (sscanf(argv[i], "--histogram=%d%c", &n, &junk) == 1 &&
683                (n == 0 || n == 1)) {
684       FLAGS_histogram = n;
685     } else if (sscanf(argv[i], "--compression_ratio=%lf%c", &d, &junk) == 1) {
686       FLAGS_compression_ratio = d;
687     } else if (sscanf(argv[i], "--use_existing_db=%d%c", &n, &junk) == 1 &&
688                (n == 0 || n == 1)) {
689       FLAGS_use_existing_db = n;
690     } else if (sscanf(argv[i], "--use_rowids=%d%c", &n, &junk) == 1 &&
691                (n == 0 || n == 1)) {
692       FLAGS_use_rowids = n;
693     } else if (sscanf(argv[i], "--num=%d%c", &n, &junk) == 1) {
694       FLAGS_num = n;
695     } else if (sscanf(argv[i], "--reads=%d%c", &n, &junk) == 1) {
696       FLAGS_reads = n;
697     } else if (sscanf(argv[i], "--value_size=%d%c", &n, &junk) == 1) {
698       FLAGS_value_size = n;
699     } else if (leveldb::Slice(argv[i]) == leveldb::Slice("--no_transaction")) {
700       FLAGS_transaction = false;
701     } else if (sscanf(argv[i], "--page_size=%d%c", &n, &junk) == 1) {
702       FLAGS_page_size = n;
703     } else if (sscanf(argv[i], "--num_pages=%d%c", &n, &junk) == 1) {
704       FLAGS_num_pages = n;
705     } else if (sscanf(argv[i], "--WAL_enabled=%d%c", &n, &junk) == 1 &&
706                (n == 0 || n == 1)) {
707       FLAGS_WAL_enabled = n;
708     } else if (strncmp(argv[i], "--db=", 5) == 0) {
709       FLAGS_db = argv[i] + 5;
710     } else {
711       std::fprintf(stderr, "Invalid flag '%s'\n", argv[i]);
712       std::exit(1);
713     }
714   }
715 
716   // Choose a location for the test database if none given with --db=<path>
717   if (FLAGS_db == nullptr) {
718     leveldb::Env::Default()->GetTestDirectory(&default_db_path);
719     default_db_path += "/dbbench";
720     FLAGS_db = default_db_path.c_str();
721   }
722 
723   leveldb::Benchmark benchmark;
724   benchmark.Run();
725   return 0;
726 }
727