1.. _myrocks_status_variables: 2 3======================== 4MyRocks Status Variables 5======================== 6 7MyRocks status variables provide details 8about the inner workings of the storage engine 9and they can be useful in tuning the storage engine 10to a particular environment. 11 12You can view these variables and their values by running: 13 14.. code-block:: mysql 15 16 mysql> SHOW STATUS LIKE 'rocksdb%'; 17 18The following global status variables are available: 19 20.. tabularcolumns:: |p{9cm}|p{6cm}| 21 22.. list-table:: 23 :header-rows: 1 24 25 * - Name 26 - Var Type 27 * - :variable:`rocksdb_rows_deleted` 28 - Numeric 29 * - :variable:`rocksdb_rows_inserted` 30 - Numeric 31 * - :variable:`rocksdb_rows_read` 32 - Numeric 33 * - :variable:`rocksdb_rows_updated` 34 - Numeric 35 * - :variable:`rocksdb_rows_expired` 36 - Numeric 37 * - :variable:`rocksdb_rows_filtered` 38 - Numeric 39 * - :variable:`rocksdb_system_rows_deleted` 40 - Numeric 41 * - :variable:`rocksdb_system_rows_inserted` 42 - Numeric 43 * - :variable:`rocksdb_system_rows_read` 44 - Numeric 45 * - :variable:`rocksdb_system_rows_updated` 46 - Numeric 47 * - :variable:`rocksdb_memtable_total` 48 - Numeric 49 * - :variable:`rocksdb_memtable_unflushed` 50 - Numeric 51 * - :variable:`rocksdb_queries_point` 52 - Numeric 53 * - :variable:`rocksdb_queries_range` 54 - Numeric 55 * - :variable:`rocksdb_covered_secondary_key_lookups` 56 - Numeric 57 * - :variable:`rocksdb_additional_compactions_trigger` 58 - Numeric 59 * - :variable:`rocksdb_block_cache_add` 60 - Numeric 61 * - :variable:`rocksdb_block_cache_add_failures` 62 - Numeric 63 * - :variable:`rocksdb_block_cache_bytes_read` 64 - Numeric 65 * - :variable:`rocksdb_block_cache_bytes_write` 66 - Numeric 67 * - :variable:`rocksdb_block_cache_data_add` 68 - Numeric 69 * - :variable:`rocksdb_block_cache_data_bytes_insert` 70 - Numeric 71 * - :variable:`rocksdb_block_cache_data_hit` 72 - Numeric 73 * - :variable:`rocksdb_block_cache_data_miss` 74 - Numeric 75 * - :variable:`rocksdb_block_cache_filter_add` 76 - Numeric 77 * - :variable:`rocksdb_block_cache_filter_bytes_evict` 78 - Numeric 79 * - :variable:`rocksdb_block_cache_filter_bytes_insert` 80 - Numeric 81 * - :variable:`rocksdb_block_cache_filter_hit` 82 - Numeric 83 * - :variable:`rocksdb_block_cache_filter_miss` 84 - Numeric 85 * - :variable:`rocksdb_block_cache_hit` 86 - Numeric 87 * - :variable:`rocksdb_block_cache_index_add` 88 - Numeric 89 * - :variable:`rocksdb_block_cache_index_bytes_evict` 90 - Numeric 91 * - :variable:`rocksdb_block_cache_index_bytes_insert` 92 - Numeric 93 * - :variable:`rocksdb_block_cache_index_hit` 94 - Numeric 95 * - :variable:`rocksdb_block_cache_index_miss` 96 - Numeric 97 * - :variable:`rocksdb_block_cache_miss` 98 - Numeric 99 * - :variable:`rocksdb_block_cache_compressed_hit` 100 - Numeric 101 * - :variable:`rocksdb_block_cache_compressed_miss` 102 - Numeric 103 * - :variable:`rocksdb_bloom_filter_prefix_checked` 104 - Numeric 105 * - :variable:`rocksdb_bloom_filter_prefix_useful` 106 - Numeric 107 * - :variable:`rocksdb_bloom_filter_useful` 108 - Numeric 109 * - :variable:`rocksdb_bytes_read` 110 - Numeric 111 * - :variable:`rocksdb_bytes_written` 112 - Numeric 113 * - :variable:`rocksdb_compact_read_bytes` 114 - Numeric 115 * - :variable:`rocksdb_compact_write_bytes` 116 - Numeric 117 * - :variable:`rocksdb_compaction_key_drop_new` 118 - Numeric 119 * - :variable:`rocksdb_compaction_key_drop_obsolete` 120 - Numeric 121 * - :variable:`rocksdb_compaction_key_drop_user` 122 - Numeric 123 * - :variable:`rocksdb_flush_write_bytes` 124 - Numeric 125 * - :variable:`rocksdb_get_hit_l0` 126 - Numeric 127 * - :variable:`rocksdb_get_hit_l1` 128 - Numeric 129 * - :variable:`rocksdb_get_hit_l2_and_up` 130 - Numeric 131 * - :variable:`rocksdb_get_updates_since_calls` 132 - Numeric 133 * - :variable:`rocksdb_iter_bytes_read` 134 - Numeric 135 * - :variable:`rocksdb_memtable_hit` 136 - Numeric 137 * - :variable:`rocksdb_memtable_miss` 138 - Numeric 139 * - :variable:`rocksdb_no_file_closes` 140 - Numeric 141 * - :variable:`rocksdb_no_file_errors` 142 - Numeric 143 * - :variable:`rocksdb_no_file_opens` 144 - Numeric 145 * - :variable:`rocksdb_num_iterators` 146 - Numeric 147 * - :variable:`rocksdb_number_block_not_compressed` 148 - Numeric 149 * - :variable:`rocksdb_number_db_next` 150 - Numeric 151 * - :variable:`rocksdb_number_db_next_found` 152 - Numeric 153 * - :variable:`rocksdb_number_db_prev` 154 - Numeric 155 * - :variable:`rocksdb_number_db_prev_found` 156 - Numeric 157 * - :variable:`rocksdb_number_db_seek` 158 - Numeric 159 * - :variable:`rocksdb_number_db_seek_found` 160 - Numeric 161 * - :variable:`rocksdb_number_deletes_filtered` 162 - Numeric 163 * - :variable:`rocksdb_number_keys_read` 164 - Numeric 165 * - :variable:`rocksdb_number_keys_updated` 166 - Numeric 167 * - :variable:`rocksdb_number_keys_written` 168 - Numeric 169 * - :variable:`rocksdb_number_merge_failures` 170 - Numeric 171 * - :variable:`rocksdb_number_multiget_bytes_read` 172 - Numeric 173 * - :variable:`rocksdb_number_multiget_get` 174 - Numeric 175 * - :variable:`rocksdb_number_multiget_keys_read` 176 - Numeric 177 * - :variable:`rocksdb_number_reseeks_iteration` 178 - Numeric 179 * - :variable:`rocksdb_number_sst_entry_delete` 180 - Numeric 181 * - :variable:`rocksdb_number_sst_entry_merge` 182 - Numeric 183 * - :variable:`rocksdb_number_sst_entry_other` 184 - Numeric 185 * - :variable:`rocksdb_number_sst_entry_put` 186 - Numeric 187 * - :variable:`rocksdb_number_sst_entry_singledelete` 188 - Numeric 189 * - :variable:`rocksdb_number_stat_computes` 190 - Numeric 191 * - :variable:`rocksdb_number_superversion_acquires` 192 - Numeric 193 * - :variable:`rocksdb_number_superversion_cleanups` 194 - Numeric 195 * - :variable:`rocksdb_number_superversion_releases` 196 - Numeric 197 * - :variable:`rocksdb_rate_limit_delay_millis` 198 - Numeric 199 * - :variable:`rocksdb_row_lock_deadlocks` 200 - Numeric 201 * - :variable:`rocksdb_row_lock_wait_timeouts` 202 - Numeric 203 * - :variable:`rocksdb_snapshot_conflict_errors` 204 - Numeric 205 * - :variable:`rocksdb_stall_l0_file_count_limit_slowdowns` 206 - Numeric 207 * - :variable:`rocksdb_stall_locked_l0_file_count_limit_slowdowns` 208 - Numeric 209 * - :variable:`rocksdb_stall_l0_file_count_limit_stops` 210 - Numeric 211 * - :variable:`rocksdb_stall_locked_l0_file_count_limit_stops` 212 - Numeric 213 * - :variable:`rocksdb_stall_pending_compaction_limit_stops` 214 - Numeric 215 * - :variable:`rocksdb_stall_pending_compaction_limit_slowdowns` 216 - Numeric 217 * - :variable:`rocksdb_stall_memtable_limit_stops` 218 - Numeric 219 * - :variable:`rocksdb_stall_memtable_limit_slowdowns` 220 - Numeric 221 * - :variable:`rocksdb_stall_total_stops` 222 - Numeric 223 * - :variable:`rocksdb_stall_total_slowdowns` 224 - Numeric 225 * - :variable:`rocksdb_stall_micros` 226 - Numeric 227 * - :variable:`rocksdb_wal_bytes` 228 - Numeric 229 * - :variable:`rocksdb_wal_group_syncs` 230 - Numeric 231 * - :variable:`rocksdb_wal_synced` 232 - Numeric 233 * - :variable:`rocksdb_write_other` 234 - Numeric 235 * - :variable:`rocksdb_write_self` 236 - Numeric 237 * - :variable:`rocksdb_write_timedout` 238 - Numeric 239 * - :variable:`rocksdb_write_wal` 240 - Numeric 241 242.. variable:: rocksdb_rows_deleted 243 244This variable shows the number of rows that were deleted from MyRocks tables. 245 246.. variable:: rocksdb_rows_inserted 247 248This variable shows the number of rows that were inserted into MyRocks tables. 249 250.. variable:: rocksdb_rows_read 251 252This variable shows the number of rows that were read from MyRocks tables. 253 254.. variable:: rocksdb_rows_updated 255 256This variable shows the number of rows that were updated in MyRocks tables. 257 258.. variable:: rocksdb_rows_expired 259 260This variable shows the number of expired rows in MyRocks tables. 261 262.. variable:: rocksdb_rows_filtered 263 264This variable shows the number of rows that were filtered out for TTL in 265MyRocks tables. 266 267.. variable:: rocksdb_system_rows_deleted 268 269This variable shows the number of rows that were deleted 270from MyRocks system tables. 271 272.. variable:: rocksdb_system_rows_inserted 273 274This variable shows the number of rows that were inserted 275into MyRocks system tables. 276 277.. variable:: rocksdb_system_rows_read 278 279This variable shows the number of rows that were read 280from MyRocks system tables. 281 282.. variable:: rocksdb_system_rows_updated 283 284This variable shows the number of rows that were updated 285in MyRocks system tables. 286 287.. variable:: rocksdb_memtable_total 288 289This variable shows the memory usage, in bytes, of all memtables. 290 291.. variable:: rocksdb_memtable_unflushed 292 293This variable shows the memory usage, in bytes, of all unflushed memtables. 294 295.. variable:: rocksdb_queries_point 296 297This variable shows the number of single row queries. 298 299.. variable:: rocksdb_queries_range 300 301This variable shows the number of multi/range row queries. 302 303.. variable:: rocksdb_covered_secondary_key_lookups 304 305This variable shows the number of lookups via secondary index that were able to 306return all fields requested directly from the secondary index when the 307secondary index contained a field that is only a prefix of the 308``varchar`` column. 309 310.. variable:: rocksdb_additional_compactions_trigger 311 312This variable shows the number of triggered additional compactions. 313MyRocks triggers an additional compaction if (number of deletions / number of entries) > (rocksdb_compaction_sequential_deletes / rocksdb_compaction_sequential_deletes_window) 314in the SST file. 315 316.. variable:: rocksdb_block_cache_add 317 318This variable shows the number of blocks added to block cache. 319 320.. variable:: rocksdb_block_cache_add_failures 321 322This variable shows the number of failures when adding blocks to block cache. 323 324.. variable:: rocksdb_block_cache_bytes_read 325 326This variable shows the number of bytes read from cache. 327 328.. variable:: rocksdb_block_cache_bytes_write 329 330This variable shows the number of bytes written into cache. 331 332.. variable:: rocksdb_block_cache_data_add 333 334This variable shows the number of data blocks added to block cache. 335 336.. variable:: rocksdb_block_cache_data_bytes_insert 337 338This variable shows the number of bytes of data blocks inserted into cache. 339 340.. variable:: rocksdb_block_cache_data_hit 341 342This variable shows the number of cache hits when accessing the 343data block from the block cache. 344 345.. variable:: rocksdb_block_cache_data_miss 346 347This variable shows the number of cache misses when accessing the 348data block from the block cache. 349 350.. variable:: rocksdb_block_cache_filter_add 351 352This variable shows the number of filter blocks added to block cache. 353 354.. variable:: rocksdb_block_cache_filter_bytes_evict 355 356This variable shows the number of bytes of bloom filter blocks 357removed from cache. 358 359.. variable:: rocksdb_block_cache_filter_bytes_insert 360 361This variable shows the number of bytes of bloom filter blocks 362inserted into cache. 363 364.. variable:: rocksdb_block_cache_filter_hit 365 366This variable shows the number of times cache hit when accessing filter block 367from block cache. 368 369.. variable:: rocksdb_block_cache_filter_miss 370 371This variable shows the number of times cache miss when accessing filter 372block from block cache. 373 374.. variable:: rocksdb_block_cache_hit 375 376This variable shows the total number of block cache hits. 377 378.. variable:: rocksdb_block_cache_index_add 379 380This variable shows the number of index blocks added to block cache. 381 382.. variable:: rocksdb_block_cache_index_bytes_evict 383 384This variable shows the number of bytes of index block erased from cache. 385 386.. variable:: rocksdb_block_cache_index_bytes_insert 387 388This variable shows the number of bytes of index blocks inserted into cache. 389 390.. variable:: rocksdb_block_cache_index_hit 391 392This variable shows the total number of block cache index hits. 393 394.. variable:: rocksdb_block_cache_index_miss 395 396This variable shows the number of times cache hit when accessing index 397block from block cache. 398 399.. variable:: rocksdb_block_cache_miss 400 401This variable shows the total number of block cache misses. 402 403.. variable:: rocksdb_block_cache_compressed_hit 404 405This variable shows the number of hits in the compressed block cache. 406 407.. variable:: rocksdb_block_cache_compressed_miss 408 409This variable shows the number of misses in the compressed block cache. 410 411.. variable:: rocksdb_bloom_filter_prefix_checked 412 413This variable shows the number of times bloom was checked before 414creating iterator on a file. 415 416.. variable:: rocksdb_bloom_filter_prefix_useful 417 418This variable shows the number of times the check was useful in avoiding 419iterator creation (and thus likely IOPs). 420 421.. variable:: rocksdb_bloom_filter_useful 422 423This variable shows the number of times bloom filter has avoided file reads. 424 425.. variable:: rocksdb_bytes_read 426 427This variable shows the total number of uncompressed bytes read. It could be 428either from memtables, cache, or table files. 429 430.. variable:: rocksdb_bytes_written 431 432This variable shows the total number of uncompressed bytes written. 433 434.. variable:: rocksdb_compact_read_bytes 435 436This variable shows the number of bytes read during compaction 437 438.. variable:: rocksdb_compact_write_bytes 439 440This variable shows the number of bytes written during compaction. 441 442.. variable:: rocksdb_compaction_key_drop_new 443 444This variable shows the number of key drops during compaction because 445it was overwritten with a newer value. 446 447.. variable:: rocksdb_compaction_key_drop_obsolete 448 449This variable shows the number of key drops during compaction because 450it was obsolete. 451 452.. variable:: rocksdb_compaction_key_drop_user 453 454This variable shows the number of key drops during compaction because 455user compaction function has dropped the key. 456 457.. variable:: rocksdb_flush_write_bytes 458 459This variable shows the number of bytes written during flush. 460 461.. variable:: rocksdb_get_hit_l0 462 463This variable shows the number of ``Get()`` queries served by L0. 464 465.. variable:: rocksdb_get_hit_l1 466 467This variable shows the number of ``Get()`` queries served by L1. 468 469.. variable:: rocksdb_get_hit_l2_and_up 470 471This variable shows the number of ``Get()`` queries served by L2 and up. 472 473.. variable:: rocksdb_get_updates_since_calls 474 475This variable shows the number of calls to ``GetUpdatesSince`` function. 476Useful to keep track of transaction log iterator refreshes 477 478.. variable:: rocksdb_iter_bytes_read 479 480This variable shows the number of uncompressed bytes read from an iterator. 481It includes size of key and value. 482 483.. variable:: rocksdb_memtable_hit 484 485This variable shows the number of memtable hits. 486 487.. variable:: rocksdb_memtable_miss 488 489This variable shows the number of memtable misses. 490 491.. variable:: rocksdb_no_file_closes 492 493This variable shows the number of time file were closed. 494 495.. variable:: rocksdb_no_file_errors 496 497This variable shows number of errors trying to read in data from an sst file. 498 499.. variable:: rocksdb_no_file_opens 500 501This variable shows the number of time file were opened. 502 503.. variable:: rocksdb_num_iterators 504 505This variable shows the number of currently open iterators. 506 507.. variable:: rocksdb_number_block_not_compressed 508 509This variable shows the number of uncompressed blocks. 510 511.. variable:: rocksdb_number_db_next 512 513This variable shows the number of calls to ``next``. 514 515.. variable:: rocksdb_number_db_next_found 516 517This variable shows the number of calls to ``next`` that returned data. 518 519.. variable:: rocksdb_number_db_prev 520 521This variable shows the number of calls to ``prev``. 522 523.. variable:: rocksdb_number_db_prev_found 524 525This variable shows the number of calls to ``prev`` that returned data. 526 527.. variable:: rocksdb_number_db_seek 528 529This variable shows the number of calls to ``seek``. 530 531.. variable:: rocksdb_number_db_seek_found 532 533This variable shows the number of calls to ``seek`` that returned data. 534 535.. variable:: rocksdb_number_deletes_filtered 536 537This variable shows the number of deleted records that were not required to be 538written to storage because key did not exist. 539 540.. variable:: rocksdb_number_keys_read 541 542This variable shows the number of keys read. 543 544.. variable:: rocksdb_number_keys_updated 545 546This variable shows the number of keys updated, if inplace update is enabled. 547 548.. variable:: rocksdb_number_keys_written 549 550This variable shows the number of keys written to the database. 551 552.. variable:: rocksdb_number_merge_failures 553 554This variable shows the number of failures performing merge operator actions 555in RocksDB. 556 557.. variable:: rocksdb_number_multiget_bytes_read 558 559This variable shows the number of bytes read during RocksDB 560``MultiGet()`` calls. 561 562.. variable:: rocksdb_number_multiget_get 563 564This variable shows the number ``MultiGet()`` requests to RocksDB. 565 566.. variable:: rocksdb_number_multiget_keys_read 567 568This variable shows the keys read via ``MultiGet()``. 569 570.. variable:: rocksdb_number_reseeks_iteration 571 572This variable shows the number of times reseek happened inside an iteration to 573skip over large number of keys with same userkey. 574 575.. variable:: rocksdb_number_sst_entry_delete 576 577This variable shows the total number of delete markers written by MyRocks. 578 579.. variable:: rocksdb_number_sst_entry_merge 580 581This variable shows the total number of merge keys written by MyRocks. 582 583.. variable:: rocksdb_number_sst_entry_other 584 585This variable shows the total number of non-delete, non-merge, non-put keys 586written by MyRocks. 587 588.. variable:: rocksdb_number_sst_entry_put 589 590This variable shows the total number of put keys written by MyRocks. 591 592.. variable:: rocksdb_number_sst_entry_singledelete 593 594This variable shows the total number of single delete keys written by MyRocks. 595 596.. variable:: rocksdb_number_stat_computes 597 598This variable was removed in |Percona Server| :rn:`5.7.23-23`. 599 600.. variable:: rocksdb_number_superversion_acquires 601 602This variable shows the number of times the superversion structure has been 603acquired in RocksDB, this is used for tracking all of the files for the 604database. 605 606.. variable:: rocksdb_number_superversion_cleanups 607 608.. variable:: rocksdb_number_superversion_releases 609 610.. variable:: rocksdb_rate_limit_delay_millis 611 612This variable was removed in |Percona Server| :rn:`5.7.23-23`. 613 614.. variable:: rocksdb_row_lock_deadlocks 615 616This variable shows the total number of deadlocks that have been detected since the instance was started. 617 618.. variable:: rocksdb_row_lock_wait_timeouts 619 620This variable shows the total number of row lock wait timeouts that have been detected since the instance was started. 621 622.. variable:: rocksdb_snapshot_conflict_errors 623 624This variable shows the number of snapshot conflict errors occurring during 625write transactions that forces the transaction to rollback. 626 627.. variable:: rocksdb_stall_l0_file_count_limit_slowdowns 628 629This variable shows the slowdowns in write due to L0 being close to full. 630 631.. variable:: rocksdb_stall_locked_l0_file_count_limit_slowdowns 632 633This variable shows the slowdowns in write due to L0 being close to full and 634compaction for L0 is already in progress. 635 636.. variable:: rocksdb_stall_l0_file_count_limit_stops 637 638This variable shows the stalls in write due to L0 being full. 639 640.. variable:: rocksdb_stall_locked_l0_file_count_limit_stops 641 642This variable shows the stalls in write due to L0 being full and compaction 643for L0 is already in progress. 644 645.. variable:: rocksdb_stall_pending_compaction_limit_stops 646 647This variable shows the stalls in write due to hitting limits set for max 648number of pending compaction bytes. 649 650.. variable:: rocksdb_stall_pending_compaction_limit_slowdowns 651 652This variable shows the slowdowns in write due to getting close to limits set 653for max number of pending compaction bytes. 654 655.. variable:: rocksdb_stall_memtable_limit_stops 656 657This variable shows the stalls in write due to hitting max number of 658``memTables`` allowed. 659 660.. variable:: rocksdb_stall_memtable_limit_slowdowns 661 662This variable shows the slowdowns in writes due to getting close to 663max number of memtables allowed. 664 665.. variable:: rocksdb_stall_total_stops 666 667This variable shows the total number of write stalls. 668 669.. variable:: rocksdb_stall_total_slowdowns 670 671This variable shows the total number of write slowdowns. 672 673.. variable:: rocksdb_stall_micros 674 675This variable shows how long (in microseconds) the writer had to wait for 676compaction or flush to finish. 677 678.. variable:: rocksdb_wal_bytes 679 680This variables shows the number of bytes written to WAL. 681 682.. variable:: rocksdb_wal_group_syncs 683 684This variable shows the number of group commit WAL file syncs 685that have occurred. 686 687.. variable:: rocksdb_wal_synced 688 689This variable shows the number of times WAL sync was done. 690 691.. variable:: rocksdb_write_other 692 693This variable shows the number of writes processed by another thread. 694 695.. variable:: rocksdb_write_self 696 697This variable shows the number of writes that were processed 698by a requesting thread. 699 700.. variable:: rocksdb_write_timedout 701 702This variable shows the number of writes ending up with timed-out. 703 704.. variable:: rocksdb_write_wal 705 706This variable shows the number of Write calls that request WAL. 707