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