db_bench_sqlite3.cc
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 }