背景
建立视图, 方便查询
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 |
create schema dba;
create view dba.invalid_index as select indisvalid, indexrelid::regclass, indrelid::regclass, pg_get_indexdef(indexrelid) from pg_index where not indisvalid;
create view dba.ro_conflicts as select datname,pg_stat_get_db_conflict_all(oid) conflict_all,pg_stat_get_db_conflict_bufferpin(oid) conflict_bufferpin,pg_stat_get_db_conflict_lock(oid) conflict_lock,pg_stat_get_db_conflict_snapshot(oid) conflict_snapshot,pg_stat_get_db_conflict_startup_deadlock(oid) conflict_deadlock,pg_stat_get_db_conflict_tablespace(oid) conflict_tbs from pg_database;
create or replace procedure dba.tps() as $$ declare v1 int8; v2 int8; begin select txid_snapshot_xmax(txid_current_snapshot()) into v1; commit ; perform pg_sleep(1); select txid_snapshot_xmax(txid_current_snapshot()) into v2; commit ; raise notice 'tps: %' , v2-v1; end ; $$ language plpgsql ;
-- 在主节点查询 create view dba.ro_delay as select application_name,client_addr,client_port,write_lag,replay_lag,sync_state from pg_stat_replication ;
-- 在standby节点执行, 检查replay比receive的延迟 create view dba.node_delay as select * from pg_size_pretty(pg_wal_lsn_diff(pg_last_wal_receive_lsn(),pg_last_wal_replay_lsn())) as t(delay);
-- 在standby节点执行, 检查receiver接收wal比上游产生wal的延迟. create view dba.ro_delay_on_standby as select pg_size_pretty(pg_wal_lsn_diff(latest_end_lsn , received_lsn)) from pg_stat_wal_receiver;
-- 在standby节点执行, 接收wal的速度。 CREATE OR REPLACE PROCEDURE dba.wal_receive_bw() LANGUAGE plpgsql AS $ procedure $ declare v1 pg_lsn; v2 pg_lsn; begin select pg_last_wal_receive_lsn() into v1; commit ; perform pg_sleep(1); select pg_last_wal_receive_lsn() into v2; commit ; raise notice 'wal receive bw: %/s' , pg_size_pretty(pg_wal_lsn_diff(v2,v1)); end ; $ procedure $;
-- 在standby节点执行, replay wal的速度。 CREATE OR REPLACE PROCEDURE dba.wal_replay_bw() LANGUAGE plpgsql AS $ procedure $ declare v1 pg_lsn; v2 pg_lsn; begin select pg_last_wal_replay_lsn() into v1; commit ; perform pg_sleep(1); select pg_last_wal_replay_lsn() into v2; commit ; raise notice 'wal replay bw: %/s' , pg_size_pretty(pg_wal_lsn_diff(v2,v1)); end ; $ procedure $;
create view dba.topsql as select calls,total_time,total_time/calls,query from pg_stat_statements where query !~ 'rds' order by total_time desc limit 5;
create view dba.qps as with a as ( select sum (calls) s from pg_stat_statements), b as ( select sum (calls) s from pg_stat_statements , pg_sleep(1)) select b.s-a.s -- QPS from a,b;
create view dba.session_acting_cnt as select count (*) from pg_stat_activity where wait_event is not null and (backend_xid is not null or backend_xmin is not null );
create view dba.sessions as select * from pg_stat_activity where wait_event is not null and (backend_xid is not null or backend_xmin is not null );
create view dba.locks as with t_wait as ( select a.mode,a.locktype,a. database ,a.relation,a.page,a.tuple,a.classid,a.granted, a.objid,a.objsubid,a.pid,a.virtualtransaction,a.virtualxid,a.transactionid,a.fastpath, b.state,b.query,b.xact_start,b.query_start,b.usename,b.datname,b.client_addr,b.client_port,b.application_name from pg_locks a,pg_stat_activity b where a.pid=b.pid and not a.granted ), t_run as ( select a.mode,a.locktype,a. database ,a.relation,a.page,a.tuple,a.classid,a.granted, a.objid,a.objsubid,a.pid,a.virtualtransaction,a.virtualxid,a.transactionid,a.fastpath, b.state,b.query,b.xact_start,b.query_start,b.usename,b.datname,b.client_addr,b.client_port,b.application_name from pg_locks a,pg_stat_activity b where a.pid=b.pid and a.granted ), t_overlap as ( select r.* from t_wait w join t_run r on ( r.locktype is not distinct from w.locktype and r. database is not distinct from w. database and r.relation is not distinct from w.relation and r.page is not distinct from w.page and r.tuple is not distinct from w.tuple and r.virtualxid is not distinct from w.virtualxid and r.transactionid is not distinct from w.transactionid and r.classid is not distinct from w.classid and r.objid is not distinct from w.objid and r.objsubid is not distinct from w.objsubid and r.pid <> w.pid ) ), t_unionall as ( select r.* from t_overlap r union all select w.* from t_wait w ) select locktype,datname,relation::regclass,page,tuple,virtualxid,transactionid::text,classid::regclass,objid,objsubid, string_agg( 'Pid: ' || case when pid is null then 'NULL' else pid::text end ||chr(10)|| 'Lock_Granted: ' || case when granted is null then 'NULL' else granted::text end || ' , Mode: ' || case when mode is null then 'NULL' else mode::text end || ' , FastPath: ' || case when fastpath is null then 'NULL' else fastpath::text end || ' , VirtualTransaction: ' || case when virtualtransaction is null then 'NULL' else virtualtransaction::text end || ' , Session_State: ' || case when state is null then 'NULL' else state::text end ||chr(10)|| 'Username: ' || case when usename is null then 'NULL' else usename::text end || ' , Database: ' || case when datname is null then 'NULL' else datname::text end || ' , Client_Addr: ' || case when client_addr is null then 'NULL' else client_addr::text end || ' , Client_Port: ' || case when client_port is null then 'NULL' else client_port::text end || ' , Application_Name: ' || case when application_name is null then 'NULL' else application_name::text end ||chr(10)|| 'Xact_Start: ' || case when xact_start is null then 'NULL' else xact_start::text end || ' , Query_Start: ' || case when query_start is null then 'NULL' else query_start::text end || ' , Xact_Elapse: ' || case when (now()-xact_start) is null then 'NULL' else (now()-xact_start)::text end || ' , Query_Elapse: ' || case when (now()-query_start) is null then 'NULL' else (now()-query_start)::text end ||chr(10)|| 'SQL (Current SQL in Transaction): ' ||chr(10)|| case when query is null then 'NULL' else query::text end , chr(10)|| '--------' ||chr(10) order by ( case mode when 'INVALID' then 0 when 'AccessShareLock' then 1 when 'RowShareLock' then 2 when 'RowExclusiveLock' then 3 when 'ShareUpdateExclusiveLock' then 4 when 'ShareLock' then 5 when 'ShareRowExclusiveLock' then 6 when 'ExclusiveLock' then 7 when 'AccessExclusiveLock' then 8 else 0 end ) desc , ( case when granted then 0 else 1 end ) ) as lock_conflict from t_unionall group by locktype,datname,relation,page,tuple,virtualxid,transactionid::text,classid,objid,objsubid ;
create view dba.top10sizetable as select schemaname,tablename,pg_size_pretty(pg_relation_size((quote_ident(schemaname)|| '.' ||quote_ident(tablename))::regclass)) from pg_tables order by pg_relation_size((quote_ident(schemaname)|| '.' ||quote_ident(tablename))::regclass) desc limit 10;
create view dba.top10sizeindex as select schemaname,tablename,indexname,pg_size_pretty(pg_relation_size((quote_ident(schemaname)|| '.' ||quote_ident(indexname))::regclass)) from pg_indexes order by pg_relation_size((quote_ident(schemaname)|| '.' ||quote_ident(indexname))::regclass) desc limit 10;
create view dba.top10sizetableindex as select schemaname,tablename,pg_size_pretty(pg_total_relation_size((quote_ident(schemaname)|| '.' ||quote_ident(tablename))::regclass)) from pg_tables order by pg_total_relation_size((quote_ident(schemaname)|| '.' ||quote_ident(tablename))::regclass) desc limit 10;
create view dba.top10updatetable as select schemaname,relname,n_tup_upd,n_tup_del,round(n_tup_hot_upd/( case when n_tup_upd=0 then 1.0 else n_tup_upd:: numeric end ),4) from pg_stat_all_tables order by n_tup_upd+n_tup_del desc limit 10;
create view dba.top10inserttable as select schemaname,relname,n_tup_ins from pg_stat_all_tables order by n_tup_ins desc limit 10;
create view dba.top10deadtable as select schemaname,relname,n_dead_tup from pg_stat_all_tables order by n_dead_tup desc limit 10;
create view dba.top10age as select relnamespace::regnamespace,relname,pg_size_pretty(pg_relation_size(oid)),age(relfrozenxid) from pg_class where relkind= 'r' and relnamespace<> 'pg_catalog' ::regnamespace and relnamespace<> 'information_schema' ::regnamespace order by age(relfrozenxid) desc ,pg_relation_size(oid) desc limit 10;
-- 膨胀点查询 create view dba.oldestxact as select datname,usename,xact_start,query_start,backend_xid,backend_xmin, now()-xact_start as old_ts, txid_current()-least(backend_xid::text::int8,backend_xmin::text::int8) as old_xacts, query from pg_stat_activity where ltrim( lower (query), ' ' ) !~ '^vacuum' and not (query ~ 'autovacuum' and backend_type <> 'client backend' ) order by least(backend_xid::text::int8,backend_xmin::text::int8) limit 1;
-- 查询膨胀空间top 10的表 create view dba.top10bloatsizetable as SELECT current_database() AS db, schemaname, tablename, reltuples:: bigint AS tups, relpages:: bigint AS pages, otta, ROUND( CASE WHEN otta=0 OR sml.relpages=0 OR sml.relpages=otta THEN 0.0 ELSE sml.relpages/otta:: numeric END ,1) AS tbloat, CASE WHEN relpages < otta THEN 0 ELSE relpages:: bigint - otta END AS wastedpages, CASE WHEN relpages < otta THEN 0 ELSE bs*(sml.relpages-otta):: bigint END AS wastedbytes, CASE WHEN relpages < otta THEN '0 bytes' ::text ELSE pg_size_pretty((bs*(relpages-otta)):: bigint ) END AS wastedsize, iname, ituples:: bigint AS itups, ipages:: bigint AS ipages, iotta, ROUND( CASE WHEN iotta=0 OR ipages=0 OR ipages=iotta THEN 0.0 ELSE ipages/iotta:: numeric END ,1) AS ibloat, CASE WHEN ipages < iotta THEN 0 ELSE ipages:: bigint - iotta END AS wastedipages, CASE WHEN ipages < iotta THEN 0 ELSE bs*(ipages-iotta) END AS wastedibytes, CASE WHEN ipages < iotta THEN '0 bytes' ELSE pg_size_pretty((bs*(ipages-iotta)):: bigint ) END AS wastedisize, pg_size_pretty( CASE WHEN relpages < otta THEN CASE WHEN ipages < iotta THEN 0 ELSE bs*(ipages-iotta:: bigint ) END ELSE CASE WHEN ipages < iotta THEN bs*(relpages-otta:: bigint ) ELSE bs*(relpages-otta:: bigint + ipages-iotta:: bigint ) END END ) AS totalwastedbytes FROM ( SELECT nn.nspname AS schemaname, cc.relname AS tablename, COALESCE (cc.reltuples,0) AS reltuples, COALESCE (cc.relpages,0) AS relpages, COALESCE (bs,0) AS bs, COALESCE (CEIL((cc.reltuples*((datahdr+ma- ( CASE WHEN datahdr%ma=0 THEN ma ELSE datahdr%ma END ))+nullhdr2+4))/(bs-20:: float )),0) AS otta, COALESCE (c2.relname, '?' ) AS iname, COALESCE (c2.reltuples,0) AS ituples, COALESCE (c2.relpages,0) AS ipages, COALESCE (CEIL((c2.reltuples*(datahdr-12))/(bs-20:: float )),0) AS iotta -- very rough approximation, assumes all cols FROM pg_class cc JOIN pg_namespace nn ON cc.relnamespace = nn.oid AND nn.nspname <> 'information_schema' LEFT JOIN ( SELECT ma,bs,foo.nspname,foo.relname, (datawidth+(hdr+ma-( case when hdr%ma=0 THEN ma ELSE hdr%ma END ))):: numeric AS datahdr, (maxfracsum*(nullhdr+ma-( case when nullhdr%ma=0 THEN ma ELSE nullhdr%ma END ))) AS nullhdr2 FROM ( SELECT ns.nspname, tbl.relname, hdr, ma, bs, SUM ((1- coalesce (null_frac,0))* coalesce (avg_width, 2048)) AS datawidth, MAX ( coalesce (null_frac,0)) AS maxfracsum, hdr+( SELECT 1+ count (*)/8 FROM pg_stats s2 WHERE null_frac<>0 AND s2.schemaname = ns.nspname AND s2.tablename = tbl.relname ) AS nullhdr FROM pg_attribute att JOIN pg_class tbl ON att.attrelid = tbl.oid JOIN pg_namespace ns ON ns.oid = tbl.relnamespace LEFT JOIN pg_stats s ON s.schemaname=ns.nspname AND s.tablename = tbl.relname AND s.inherited= false AND s.attname=att.attname, ( SELECT ( SELECT current_setting( 'block_size' ):: numeric ) AS bs, CASE WHEN SUBSTRING (SPLIT_PART(v, ' ' , 2) FROM '#"[0-9]+.[0-9]+#"%' for '#' ) IN ( '8.0' , '8.1' , '8.2' ) THEN 27 ELSE 23 END AS hdr, CASE WHEN v ~ 'mingw32' OR v ~ '64-bit' THEN 8 ELSE 4 END AS ma FROM ( SELECT version() AS v) AS foo ) AS constants WHERE att.attnum > 0 AND tbl.relkind= 'r' GROUP BY 1,2,3,4,5 ) AS foo ) AS rs ON cc.relname = rs.relname AND nn.nspname = rs.nspname LEFT JOIN pg_index i ON indrelid = cc.oid LEFT JOIN pg_class c2 ON c2.oid = i.indexrelid ) AS sml order by wastedbytes desc limit 5;
-- 查询膨胀空间top 10的索引 create view dba.top10bloatsizeindex as SELECT current_database() AS db, schemaname, tablename, reltuples:: bigint AS tups, relpages:: bigint AS pages, otta, ROUND( CASE WHEN otta=0 OR sml.relpages=0 OR sml.relpages=otta THEN 0.0 ELSE sml.relpages/otta:: numeric END ,1) AS tbloat, CASE WHEN relpages < otta THEN 0 ELSE relpages:: bigint - otta END AS wastedpages, CASE WHEN relpages < otta THEN 0 ELSE bs*(sml.relpages-otta):: bigint END AS wastedbytes, CASE WHEN relpages < otta THEN '0 bytes' ::text ELSE pg_size_pretty((bs*(relpages-otta)):: bigint ) END AS wastedsize, iname, ituples:: bigint AS itups, ipages:: bigint AS ipages, iotta, ROUND( CASE WHEN iotta=0 OR ipages=0 OR ipages=iotta THEN 0.0 ELSE ipages/iotta:: numeric END ,1) AS ibloat, CASE WHEN ipages < iotta THEN 0 ELSE ipages:: bigint - iotta END AS wastedipages, CASE WHEN ipages < iotta THEN 0 ELSE bs*(ipages-iotta) END AS wastedibytes, CASE WHEN ipages < iotta THEN '0 bytes' ELSE pg_size_pretty((bs*(ipages-iotta)):: bigint ) END AS wastedisize, pg_size_pretty( CASE WHEN relpages < otta THEN CASE WHEN ipages < iotta THEN 0 ELSE bs*(ipages-iotta:: bigint ) END ELSE CASE WHEN ipages < iotta THEN bs*(relpages-otta:: bigint ) ELSE bs*(relpages-otta:: bigint + ipages-iotta:: bigint ) END END ) AS totalwastedbytes FROM ( SELECT nn.nspname AS schemaname, cc.relname AS tablename, COALESCE (cc.reltuples,0) AS reltuples, COALESCE (cc.relpages,0) AS relpages, COALESCE (bs,0) AS bs, COALESCE (CEIL((cc.reltuples*((datahdr+ma- ( CASE WHEN datahdr%ma=0 THEN ma ELSE datahdr%ma END ))+nullhdr2+4))/(bs-20:: float )),0) AS otta, COALESCE (c2.relname, '?' ) AS iname, COALESCE (c2.reltuples,0) AS ituples, COALESCE (c2.relpages,0) AS ipages, COALESCE (CEIL((c2.reltuples*(datahdr-12))/(bs-20:: float )),0) AS iotta -- very rough approximation, assumes all cols FROM pg_class cc JOIN pg_namespace nn ON cc.relnamespace = nn.oid AND nn.nspname <> 'information_schema' LEFT JOIN ( SELECT ma,bs,foo.nspname,foo.relname, (datawidth+(hdr+ma-( case when hdr%ma=0 THEN ma ELSE hdr%ma END ))):: numeric AS datahdr, (maxfracsum*(nullhdr+ma-( case when nullhdr%ma=0 THEN ma ELSE nullhdr%ma END ))) AS nullhdr2 FROM ( SELECT ns.nspname, tbl.relname, hdr, ma, bs, SUM ((1- coalesce (null_frac,0))* coalesce (avg_width, 2048)) AS datawidth, MAX ( coalesce (null_frac,0)) AS maxfracsum, hdr+( SELECT 1+ count (*)/8 FROM pg_stats s2 WHERE null_frac<>0 AND s2.schemaname = ns.nspname AND s2.tablename = tbl.relname ) AS nullhdr FROM pg_attribute att JOIN pg_class tbl ON att.attrelid = tbl.oid JOIN pg_namespace ns ON ns.oid = tbl.relnamespace LEFT JOIN pg_stats s ON s.schemaname=ns.nspname AND s.tablename = tbl.relname AND s.inherited= false AND s.attname=att.attname, ( SELECT ( SELECT current_setting( 'block_size' ):: numeric ) AS bs, CASE WHEN SUBSTRING (SPLIT_PART(v, ' ' , 2) FROM '#"[0-9]+.[0-9]+#"%' for '#' ) IN ( '8.0' , '8.1' , '8.2' ) THEN 27 ELSE 23 END AS hdr, CASE WHEN v ~ 'mingw32' OR v ~ '64-bit' THEN 8 ELSE 4 END AS ma FROM ( SELECT version() AS v) AS foo ) AS constants WHERE att.attnum > 0 AND tbl.relkind= 'r' GROUP BY 1,2,3,4,5 ) AS foo ) AS rs ON cc.relname = rs.relname AND nn.nspname = rs.nspname LEFT JOIN pg_index i ON indrelid = cc.oid LEFT JOIN pg_class c2 ON c2.oid = i.indexrelid ) AS sml order by wastedibytes desc limit 5;
-- 查询膨胀比例top 10的表(浪费空间大于10MB的表) create view dba.top10bloatratiotable as SELECT current_database() AS db, schemaname, tablename, reltuples:: bigint AS tups, relpages:: bigint AS pages, otta, ROUND( CASE WHEN otta=0 OR sml.relpages=0 OR sml.relpages=otta THEN 0.0 ELSE sml.relpages/otta:: numeric END ,1) AS tbloat, CASE WHEN relpages < otta THEN 0 ELSE relpages:: bigint - otta END AS wastedpages, CASE WHEN relpages < otta THEN 0 ELSE bs*(sml.relpages-otta):: bigint END AS wastedbytes, CASE WHEN relpages < otta THEN '0 bytes' ::text ELSE pg_size_pretty((bs*(relpages-otta)):: bigint ) END AS wastedsize, iname, ituples:: bigint AS itups, ipages:: bigint AS ipages, iotta, ROUND( CASE WHEN iotta=0 OR ipages=0 OR ipages=iotta THEN 0.0 ELSE ipages/iotta:: numeric END ,1) AS ibloat, CASE WHEN ipages < iotta THEN 0 ELSE ipages:: bigint - iotta END AS wastedipages, CASE WHEN ipages < iotta THEN 0 ELSE bs*(ipages-iotta) END AS wastedibytes, CASE WHEN ipages < iotta THEN '0 bytes' ELSE pg_size_pretty((bs*(ipages-iotta)):: bigint ) END AS wastedisize, pg_size_pretty( CASE WHEN relpages < otta THEN CASE WHEN ipages < iotta THEN 0 ELSE bs*(ipages-iotta:: bigint ) END ELSE CASE WHEN ipages < iotta THEN bs*(relpages-otta:: bigint ) ELSE bs*(relpages-otta:: bigint + ipages-iotta:: bigint ) END END ) AS totalwastedbytes FROM ( SELECT nn.nspname AS schemaname, cc.relname AS tablename, COALESCE (cc.reltuples,0) AS reltuples, COALESCE (cc.relpages,0) AS relpages, COALESCE (bs,0) AS bs, COALESCE (CEIL((cc.reltuples*((datahdr+ma- ( CASE WHEN datahdr%ma=0 THEN ma ELSE datahdr%ma END ))+nullhdr2+4))/(bs-20:: float )),0) AS otta, COALESCE (c2.relname, '?' ) AS iname, COALESCE (c2.reltuples,0) AS ituples, COALESCE (c2.relpages,0) AS ipages, COALESCE (CEIL((c2.reltuples*(datahdr-12))/(bs-20:: float )),0) AS iotta -- very rough approximation, assumes all cols FROM pg_class cc JOIN pg_namespace nn ON cc.relnamespace = nn.oid AND nn.nspname <> 'information_schema' LEFT JOIN ( SELECT ma,bs,foo.nspname,foo.relname, (datawidth+(hdr+ma-( case when hdr%ma=0 THEN ma ELSE hdr%ma END ))):: numeric AS datahdr, (maxfracsum*(nullhdr+ma-( case when nullhdr%ma=0 THEN ma ELSE nullhdr%ma END ))) AS nullhdr2 FROM ( SELECT ns.nspname, tbl.relname, hdr, ma, bs, SUM ((1- coalesce (null_frac,0))* coalesce (avg_width, 2048)) AS datawidth, MAX ( coalesce (null_frac,0)) AS maxfracsum, hdr+( SELECT 1+ count (*)/8 FROM pg_stats s2 WHERE null_frac<>0 AND s2.schemaname = ns.nspname AND s2.tablename = tbl.relname ) AS nullhdr FROM pg_attribute att JOIN pg_class tbl ON att.attrelid = tbl.oid JOIN pg_namespace ns ON ns.oid = tbl.relnamespace LEFT JOIN pg_stats s ON s.schemaname=ns.nspname AND s.tablename = tbl.relname AND s.inherited= false AND s.attname=att.attname, ( SELECT ( SELECT current_setting( 'block_size' ):: numeric ) AS bs, CASE WHEN SUBSTRING (SPLIT_PART(v, ' ' , 2) FROM '#"[0-9]+.[0-9]+#"%' for '#' ) IN ( '8.0' , '8.1' , '8.2' ) THEN 27 ELSE 23 END AS hdr, CASE WHEN v ~ 'mingw32' OR v ~ '64-bit' THEN 8 ELSE 4 END AS ma FROM ( SELECT version() AS v) AS foo ) AS constants WHERE att.attnum > 0 AND tbl.relkind= 'r' GROUP BY 1,2,3,4,5 ) AS foo ) AS rs ON cc.relname = rs.relname AND nn.nspname = rs.nspname LEFT JOIN pg_index i ON indrelid = cc.oid LEFT JOIN pg_class c2 ON c2.oid = i.indexrelid ) AS sml where ( CASE WHEN relpages < otta THEN 0 ELSE bs*(sml.relpages-otta):: bigint END ) >= 10240000 order by tbloat desc ,wastedbytes desc limit 5;
-- 查询膨胀比例top 10的索引(浪费空间大于10MB的索引) create view dba.top10bloatratioindex as SELECT current_database() AS db, schemaname, tablename, reltuples:: bigint AS tups, relpages:: bigint AS pages, otta, ROUND( CASE WHEN otta=0 OR sml.relpages=0 OR sml.relpages=otta THEN 0.0 ELSE sml.relpages/otta:: numeric END ,1) AS tbloat, CASE WHEN relpages < otta THEN 0 ELSE relpages:: bigint - otta END AS wastedpages, CASE WHEN relpages < otta THEN 0 ELSE bs*(sml.relpages-otta):: bigint END AS wastedbytes, CASE WHEN relpages < otta THEN '0 bytes' ::text ELSE pg_size_pretty((bs*(relpages-otta)):: bigint ) END AS wastedsize, iname, ituples:: bigint AS itups, ipages:: bigint AS ipages, iotta, ROUND( CASE WHEN iotta=0 OR ipages=0 OR ipages=iotta THEN 0.0 ELSE ipages/iotta:: numeric END ,1) AS ibloat, CASE WHEN ipages < iotta THEN 0 ELSE ipages:: bigint - iotta END AS wastedipages, CASE WHEN ipages < iotta THEN 0 ELSE bs*(ipages-iotta) END AS wastedibytes, CASE WHEN ipages < iotta THEN '0 bytes' ELSE pg_size_pretty((bs*(ipages-iotta)):: bigint ) END AS wastedisize, pg_size_pretty( CASE WHEN relpages < otta THEN CASE WHEN ipages < iotta THEN 0 ELSE bs*(ipages-iotta:: bigint ) END ELSE CASE WHEN ipages < iotta THEN bs*(relpages-otta:: bigint ) ELSE bs*(relpages-otta:: bigint + ipages-iotta:: bigint ) END END ) AS totalwastedbytes FROM ( SELECT nn.nspname AS schemaname, cc.relname AS tablename, COALESCE (cc.reltuples,0) AS reltuples, COALESCE (cc.relpages,0) AS relpages, COALESCE (bs,0) AS bs, COALESCE (CEIL((cc.reltuples*((datahdr+ma- ( CASE WHEN datahdr%ma=0 THEN ma ELSE datahdr%ma END ))+nullhdr2+4))/(bs-20:: float )),0) AS otta, COALESCE (c2.relname, '?' ) AS iname, COALESCE (c2.reltuples,0) AS ituples, COALESCE (c2.relpages,0) AS ipages, COALESCE (CEIL((c2.reltuples*(datahdr-12))/(bs-20:: float )),0) AS iotta -- very rough approximation, assumes all cols FROM pg_class cc JOIN pg_namespace nn ON cc.relnamespace = nn.oid AND nn.nspname <> 'information_schema' LEFT JOIN ( SELECT ma,bs,foo.nspname,foo.relname, (datawidth+(hdr+ma-( case when hdr%ma=0 THEN ma ELSE hdr%ma END ))):: numeric AS datahdr, (maxfracsum*(nullhdr+ma-( case when nullhdr%ma=0 THEN ma ELSE nullhdr%ma END ))) AS nullhdr2 FROM ( SELECT ns.nspname, tbl.relname, hdr, ma, bs, SUM ((1- coalesce (null_frac,0))* coalesce (avg_width, 2048)) AS datawidth, MAX ( coalesce (null_frac,0)) AS maxfracsum, hdr+( SELECT 1+ count (*)/8 FROM pg_stats s2 WHERE null_frac<>0 AND s2.schemaname = ns.nspname AND s2.tablename = tbl.relname ) AS nullhdr FROM pg_attribute att JOIN pg_class tbl ON att.attrelid = tbl.oid JOIN pg_namespace ns ON ns.oid = tbl.relnamespace LEFT JOIN pg_stats s ON s.schemaname=ns.nspname AND s.tablename = tbl.relname AND s.inherited= false AND s.attname=att.attname, ( SELECT ( SELECT current_setting( 'block_size' ):: numeric ) AS bs, CASE WHEN SUBSTRING (SPLIT_PART(v, ' ' , 2) FROM '#"[0-9]+.[0-9]+#"%' for '#' ) IN ( '8.0' , '8.1' , '8.2' ) THEN 27 ELSE 23 END AS hdr, CASE WHEN v ~ 'mingw32' OR v ~ '64-bit' THEN 8 ELSE 4 END AS ma FROM ( SELECT version() AS v) AS foo ) AS constants WHERE att.attnum > 0 AND tbl.relkind= 'r' GROUP BY 1,2,3,4,5 ) AS foo ) AS rs ON cc.relname = rs.relname AND nn.nspname = rs.nspname LEFT JOIN pg_index i ON indrelid = cc.oid LEFT JOIN pg_class c2 ON c2.oid = i.indexrelid ) AS sml where ( CASE WHEN ipages < iotta THEN 0 ELSE bs*(ipages-iotta) END ) >= 10240000 order by ibloat desc ,wastedibytes desc limit 5;
create view dba.seqs as select max_value-last_value,* from pg_sequences order by max_value-last_value ;
-- 查询没有使用过的大于1MB的索引 top 10 (注意, PK、UK如果只是用于约束, 可能不会被统计计数,但是不能删掉) create view dba.top10notusedidx as select pg_size_pretty(pg_relation_size(indexrelid)),* from pg_stat_all_indexes where pg_relation_size(indexrelid)>=1024000 and (idx_scan=0 or idx_tup_read=0 or idx_tup_fetch=0) and schemaname not in ( 'pg_toast' , 'pg_catalog' ) order by pg_relation_size(indexrelid) desc limit 10;
-- 查询没有使用过的大于1MB的表 top 10 create view dba.top10notusedtab as select pg_size_pretty(pg_relation_size(relid)),* from pg_stat_all_tables where pg_relation_size(relid)>=1024000 and seq_scan=0 and idx_scan=0 and schemaname not in ( 'pg_toast' , 'pg_catalog' , 'information_schema' ) order by pg_relation_size(relid) desc limit 10;
-- 查询热表top 10 create view dba.top10hottab as select pg_size_pretty(pg_relation_size(relid)),* from pg_stat_all_tables where schemaname not in ( 'pg_toast' , 'pg_catalog' , 'information_schema' ) order by seq_scan+idx_scan desc , pg_relation_size(relid) desc limit 10;
-- 查询大于1MB的冷表top 10 create view dba.top10coldtab as select pg_size_pretty(pg_relation_size(relid)),* from pg_stat_all_tables where schemaname not in ( 'pg_toast' , 'pg_catalog' , 'information_schema' ) and pg_relation_size(relid)>=1024000 order by seq_scan+idx_scan,pg_relation_size(relid) desc limit 10;
-- 查询热索引top 10 create view dba.top10hotidx as select pg_size_pretty(pg_relation_size(indexrelid)),* from pg_stat_all_indexes where schemaname not in ( 'pg_toast' , 'pg_catalog' ) order by idx_scan+idx_tup_read+idx_tup_fetch desc , pg_relation_size(indexrelid) desc limit 10;
-- 查询大于1MB的冷索引top 10(注意, PK、UK如果只是用于约束, 可能不会被统计计数,但是不能删掉) create view dba.top10coldidx as select pg_size_pretty(pg_relation_size(indexrelid)),* from pg_stat_all_indexes where pg_relation_size(indexrelid)>=1024000 and schemaname not in ( 'pg_toast' , 'pg_catalog' ) order by idx_scan+idx_tup_read+idx_tup_fetch , pg_relation_size(indexrelid) desc limit 10;
-- freeze风暴预测相关的3个视图 create view dba.v_freeze as select e.*, a.* from ( select current_setting( 'autovacuum_freeze_max_age' ):: int as v1, -- 如果表的事务ID年龄大于该值, 即使未开启autovacuum也会强制触发FREEZE, 并告警Preventing Transaction ID Wraparound Failures current_setting( 'autovacuum_multixact_freeze_max_age' ):: int as v2, -- 如果表的并行事务ID年龄大于该值, 即使未开启autovacuum也会强制触发FREEZE, 并告警Preventing Transaction ID Wraparound Failures current_setting( 'vacuum_freeze_min_age' ):: int as v3, -- 手动或自动垃圾回收时, 如果记录的事务ID年龄大于该值, 将被FREEZE current_setting( 'vacuum_multixact_freeze_min_age' ):: int as v4, -- 手动或自动垃圾回收时, 如果记录的并行事务ID年龄大于该值, 将被FREEZE current_setting( 'vacuum_freeze_table_age' ):: int as v5, -- 手动垃圾回收时, 如果表的事务ID年龄大于该值, 将触发FREEZE. 该参数的上限值为 %95 autovacuum_freeze_max_age current_setting( 'vacuum_multixact_freeze_table_age' ):: int as v6, -- 手动垃圾回收时, 如果表的并行事务ID年龄大于该值, 将触发FREEZE. 该参数的上限值为 %95 autovacuum_multixact_freeze_max_age current_setting( 'autovacuum_vacuum_cost_delay' ) as v7, -- 自动垃圾回收时, 每轮回收周期后的一个休息时间, 主要防止垃圾回收太耗资源. -1 表示沿用vacuum_cost_delay的设置 current_setting( 'autovacuum_vacuum_cost_limit' ) as v8, -- 自动垃圾回收时, 每轮回收周期设多大限制, 限制由vacuum_cost_page_hit,vacuum_cost_page_missvacuum_cost_page_dirty参数以及周期内的操作决定. -1 表示沿用vacuum_cost_limit的设置 current_setting( 'vacuum_cost_delay' ) as v9, -- 手动垃圾回收时, 每轮回收周期后的一个休息时间, 主要防止垃圾回收太耗资源. current_setting( 'vacuum_cost_limit' ) as v10, -- 手动垃圾回收时, 每轮回收周期设多大限制, 限制由vacuum_cost_page_hit,vacuum_cost_page_missvacuum_cost_page_dirty参数以及周期内的操作决定. current_setting( 'autovacuum' ) as autovacuum -- 是否开启自动垃圾回收 ) a, LATERAL ( -- LATERAL 允许你在这个SUBQUERY中直接引用前面的table, subquery中的column select pg_size_pretty(pg_total_relation_size(oid)) sz, -- 表的大小(含TOAST, 索引) oid::regclass as reloid, -- 表名(物化视图) relkind, -- r=表, m=物化视图 coalesce ( least( substring (reloptions::text, 'autovacuum_freeze_max_age=(\d+)' ):: int , substring (reloptions::text, 'autovacuum_freeze_table_age=(\d+)' ):: int ), a.v1 ) - age( case when relfrozenxid::text:: int <3 then null else relfrozenxid end ) as remain_ages_xid, -- 再产生多少个事务后, 自动垃圾回收会触发FREEZE, 起因为事务ID coalesce ( least( substring (reloptions::text, 'autovacuum_multixact_freeze_max_age=(\d+)' ):: int , substring (reloptions::text, 'autovacuum_multixact_freeze_table_age=(\d+)' ):: int ), a.v2 ) - age( case when relminmxid::text:: int <3 then null else relminmxid end ) as remain_ages_mxid, -- 再产生多少个事务后, 自动垃圾回收会触发FREEZE, 起因为并发事务ID coalesce ( least( substring (reloptions::text, 'autovacuum_freeze_min_age=(\d+)' ):: int ), a.v3 ) as xid_lower_to_minage, -- 如果触发FREEZE, 该表的事务ID年龄会降到多少 coalesce ( least( substring (reloptions::text, 'autovacuum_multixact_freeze_min_age=(\d+)' ):: int ), a.v4 ) as mxid_lower_to_minage, -- 如果触发FREEZE, 该表的并行事务ID年龄会降到多少 case when v5 <= age( case when relfrozenxid::text:: int <3 then null else relfrozenxid end ) then 'YES' else 'NOT' end as vacuum_trigger_freeze1, -- 如果手工执行VACUUM, 是否会触发FREEZE, 触发起因(事务ID年龄达到阈值) case when v6 <= age( case when relminmxid::text:: int <3 then null else relminmxid end ) then 'YES' else 'NOT' end as vacuum_trigger_freeze2, -- 如果手工执行VACUUM, 是否会触发FREEZE, 触发起因(并行事务ID年龄达到阈值) reloptions -- 表级参数, 优先. 例如是否开启自动垃圾回收, autovacuum_freeze_max_age, autovacuum_freeze_table_age, autovacuum_multixact_freeze_max_age, autovacuum_multixact_freeze_table_age from pg_class where relkind in ( 'r' , 'm' ) ) e order by least(e.remain_ages_xid , e.remain_ages_mxid), -- 排在越前, 越先触发自动FREEZE, 即风暴来临的预测 pg_total_relation_size(reloid) desc -- 同样剩余年龄, 表越大, 排越前 ;
create view dba.v_freeze_stat as select wb, -- 第几个BATCH, 每个batch代表流逝100万个事务 cnt, -- 这个batch 有多少表 pg_size_pretty(ssz) as ssz1, -- 这个batch 这些 表+TOAST+索引 有多少容量 pg_size_pretty(ssz) as ssz2, -- 这个batch FREEZE 会导致多少读IO pg_size_pretty(ssz*3) as ssz3, -- 这个batch FREEZE 最多可能会导致多少写IO (通常三份 : 数据文件, WAL FULL PAGE, WAL) pg_size_pretty(min_sz) as ssz4, -- 这个batch 最小的表多大 pg_size_pretty(max_sz) as ssz5, -- 这个batch 最大的表多大 pg_size_pretty(avg_sz) as ssz6, -- 这个batch 平均表多大 pg_size_pretty(stddev_sz) as ssz7, -- 这个batch 表大小的方差, 越大, 说明表大小差异化明显 min_rest_age, -- 这个batch 距离自动FREEZE最低剩余事务数 max_rest_age, -- 这个batch 距离自动FREEZE最高剩余事务数 stddev_rest_age, -- 这个batch 距离自动FREEZE剩余事务数的方差, 越小,说明这个batch触发freeze将越平缓, 越大, 说明这个batch将有可能在某些点集中触发freeze (但是可能集中触发的都是小表) corr_rest_age_sz, -- 表大小与距离自动freeze剩余事务数的相关性,相关性越强(值趋向1或-1) stddev_rest_age 与 sz7 说明的问题越有价值 round(100*(ssz/( sum (ssz) over ())), 2)|| ' %' as ratio -- 这个BATCH的容量占比,占比如果非常不均匀,说明有必要调整表级FREEZE参数,让占比均匀化 from ( select a.*, b.* from ( select min (least(remain_ages_xid, remain_ages_mxid)) as v_min, -- 整个数据库中离自动FREEZE的 最小 剩余事务ID数 max (least(remain_ages_xid, remain_ages_mxid)) as v_max -- 整个数据库中离自动FREEZE的 最大 剩余事务ID数 from v_freeze ) as a, LATERAL ( -- 高级SQL select width_bucket( least(remain_ages_xid, remain_ages_mxid), a.v_min, a.v_max, greatest((a.v_max-a.v_min)/1000000, 1) -- 100万个事务, 如果要更改统计例如,修改这个值即可 ) as wb, count (*) as cnt, sum (pg_total_relation_size(reloid)) as ssz, stddev_samp(pg_total_relation_size(reloid) order by least(remain_ages_xid, remain_ages_mxid)) as stddev_sz, min (pg_total_relation_size(reloid)) as min_sz, max (pg_total_relation_size(reloid)) as max_sz, avg (pg_total_relation_size(reloid)) as avg_sz, min (least(remain_ages_xid, remain_ages_mxid)) as min_rest_age, max (least(remain_ages_xid, remain_ages_mxid)) as max_rest_age, stddev_samp(least(remain_ages_xid, remain_ages_mxid) order by least(remain_ages_xid, remain_ages_mxid)) as stddev_rest_age, corr(least(remain_ages_xid, remain_ages_mxid), pg_total_relation_size(reloid)) as corr_rest_age_sz from v_freeze group by wb ) as b ) t order by wb;
create view dba.v_freeze_stat_detail as select pg_size_pretty(t.ssz) as ssz2, -- 这个batch FREEZE 会导致多少读IO (表+TOAST+索引) pg_size_pretty(t.ssz*3) as ssz3, -- 这个batch FREEZE 最多可能会导致多少写IO (通常三份 : 数据文件, WAL FULL PAGE, WAL) pg_size_pretty(t.ssz_sum) as ssz4, -- 所有batch 所有表的总大小 (表+TOAST+索引) round(100*(t.ssz/t.ssz_sum), 2)|| ' %' as ratio_batch, -- 这个BATCH的容量占比,目标是让所有BATCH占比尽量一致 round(100*(pg_total_relation_size(t.reloid)/t.ssz), 2)|| ' %' as ratio_table, -- 这个表占整个batch的容量占比,大表尽量错开freeze t.* from ( select a.*, b.* from ( select min (least(remain_ages_xid, remain_ages_mxid)) as v_min, -- 整个数据库中离自动FREEZE的 最小 剩余事务ID数 max (least(remain_ages_xid, remain_ages_mxid)) as v_max -- 整个数据库中离自动FREEZE的 最大 剩余事务ID数 from v_freeze ) as a, LATERAL ( -- 高级SQL select count (*) over w as cnt, -- 这个batch 有多少表 sum (pg_total_relation_size(reloid)) over () as ssz_sum, -- 所有batch 所有表的总大小 (表+TOAST+索引) sum (pg_total_relation_size(reloid)) over w as ssz, -- 这个batch 的表大小总和 (表+TOAST+索引) pg_size_pretty( min (pg_total_relation_size(reloid)) over w) as min_sz, -- 这个batch 最小的表多大 pg_size_pretty( max (pg_total_relation_size(reloid)) over w) as max_sz, -- 这个batch 最大的表多大 pg_size_pretty( avg (pg_total_relation_size(reloid)) over w) as avg_sz, -- 这个batch 平均表多大 pg_size_pretty(stddev_samp(pg_total_relation_size(reloid)) over w) as stddev_sz, -- 这个batch 表大小的方差, 越大, 说明表大小差异化明显 min (least(remain_ages_xid, remain_ages_mxid)) over w as min_rest_age, -- 这个batch 距离自动FREEZE最低剩余事务数 max (least(remain_ages_xid, remain_ages_mxid)) over w as max_rest_age, -- 这个batch 距离自动FREEZE最高剩余事务数 stddev_samp(least(remain_ages_xid, remain_ages_mxid)) over w as stddev_rest_age, -- 这个batch 距离自动FREEZE剩余事务数的方差, 越小,说明这个batch触发freeze将越平缓, 越大, 说明这个batch将有可能在某些点集中触发freeze (但是可能集中触发的都是小表) corr(least(remain_ages_xid, remain_ages_mxid), pg_total_relation_size(reloid)) over w as corr_rest_age_sz, -- 表大小与距离自动freeze剩余事务数的相关性,相关性越强(值趋向1或-1) stddev_rest_age 与 stddev_sz 说明的问题越有价值 t1.* from ( select width_bucket( least(tt.remain_ages_xid, tt.remain_ages_mxid), a.v_min, a.v_max, greatest((a.v_max-a.v_min)/1000000, 1) -- 100万个事务, 如果要更改统计例如,修改这个值即可 ) as wb, -- 第几个BATCH, 每个batch代表流逝100万个事务 * from v_freeze tt ) as t1 window w as ( partition by t1.wb ) ) as b ) t order by t.wb, least(t.remain_ages_xid, t.remain_ages_mxid), pg_total_relation_size(t.reloid) desc ;
create view dba.top20freezebigtable as select relowner::regrole, relnamespace::regnamespace, relname, age(relfrozenxid),pg_size_pretty(pg_total_relation_size(oid)) , -- 当前年龄 coalesce ( least( substring (reloptions::text, 'autovacuum_freeze_max_age=(\d+)' ):: int , substring (reloptions::text, 'autovacuum_freeze_table_age=(\d+)' ):: int ), current_setting( 'autovacuum_freeze_max_age' ):: int ) - age( case when relfrozenxid::text:: int <3 then null else relfrozenxid end ) as remain_ages_xid, -- 再产生多少个事务后, 自动垃圾回收会触发FREEZE, 起因为事务ID coalesce ( least( substring (reloptions::text, 'autovacuum_freeze_min_age=(\d+)' ):: int ), current_setting( 'vacuum_freeze_min_age' ):: int ) as xid_lower_to_minage -- 如果触发FREEZE, 该表的事务ID年龄会降到多少 from pg_class where relkind= 'r' order by pg_total_relation_size(oid) desc limit 20;
-- 未归档wal文件 create view dba.arch_undone as select * from pg_ls_archive_statusdir() where name !~ 'done$' ;
-- 归档任务状态 create view dba.arch_status as select * from pg_stat_get_archiver();
-- wal空间占用 create view dba.walsize as select pg_size_pretty( sum ( size )) from pg_ls_waldir();
-- 复制槽状态(是否有未使用复制槽, 可能导致wal日志目录暴涨(不清理)) create view dba.repslots as select * from pg_replication_slots ;
-- 系统强制保留wal大小 create view dba.wal_keep_size as with a as ( select setting from pg_settings where name = 'wal_keep_segments' ) , b as ( select setting,unit from pg_settings where name = 'wal_segment_size' ) select pg_size_pretty(a.setting::int8*b.setting::int8) from a,b;
-- 系统动态检查点最大wal保留大小 create view dba.max_wal_size as select setting|| ' ' ||unit from pg_settings where name = 'max_wal_size' ;
-- 长事务、prepared statement create view dba.long_snapshot as with a as ( select min ( transaction ::Text::int8) m from pg_prepared_xacts ), b as ( select txid_snapshot_xmin(txid_current_snapshot())::text::int8 as m), c as ( select min (least(backend_xid::text::int8,backend_xmin::text::int8)) m from pg_stat_activity ), d as ( select datname,usename,pid,query_start,xact_start,now(),wait_event,query from pg_stat_activity where backend_xid is not null or backend_xmin is not null order by least(backend_xid::text::int8,backend_xmin::text::int8) limit 1), e as ( select * from pg_prepared_xacts order by transaction ::Text::int8 limit 1) select b.m-least(a.m,c.m),d.*,e.* from a,b,c,d left join e on (1=1); |
常用查询
1、查询只读节点延迟
1 2 3 4 5 6 7 8 |
-- 在主节点查询 select * from dba.ro_delay;
-- 在只读节点查询 set lock_timeout= '10ms' ; set statement_timeout= '2s' ; select * from dba.node_delay; select * from dba.ro_delay_on_standby; |
2、查询top query, 优化之首
1 |
select * from dba.topsql; |
3、重置top query统计计数器(通常在高峰期来临前可以重置,防止结果干扰)
1 |
select pg_stat_statements_reset(); |
4、查询 qps , 在psql 终端可以每秒打印一次
1 2 |
select * from dba.qps; \watch 1 |
4.1、查询tps
1 |
call dba.tps(); |
5、查询活跃会话数, 如果超过CPU核数, 说明数据库非常非常繁忙, 需要注意优化
1 |
select * from dba.session_acting_cnt; |
6、当前活跃会话
1 |
select * from dba.sessions; |
7、查询锁等待, 如果有大量长时间等待, 需要注意业务逻辑是否有问题
1 |
select * from dba.locks; |
8、查询占用空间top 10的表
1 |
select * from dba.top10sizetable; |
9、查询占用空间top 10的索引
1 |
select * from dba.top10sizeindex; |
10、查询占用空间top 10的表(含索引)
1 |
select * from dba.top10sizetableindex; |
11、查询膨胀空间top 10的表
1 |
select * from dba.top10bloatsizetable; |
12、查询膨胀空间top 10的索引
1 |
select * from dba.top10bloatsizeindex; |
13、查询膨胀比例top 10的表
1 |
select * from dba.top10bloatratiotable; |
14、查询膨胀比例top 10的索引
1 |
select * from dba.top10bloatratioindex; |
15、查询更新和删除记录条数top 10的表
1 |
select * from dba.top10updatetable; |
16、查询插入记录条数top 10的表
1 |
select * from dba.top10inserttable; |
17、查询脏记录条数top 10的表
1 |
select * from dba.top10deadtable; |
18、查询年龄top 10的表
1 |
select * from dba.top10age; |
19、查询当前的最老事务距离当前时间、距离当前事务数, 说明膨胀空间大小, 越大可能导致越多膨胀垃圾.
1 |
select * from dba.oldestxact; select * from pg_prepared_xacts; |
20、查询序列的剩余空间
1 |
select * from dba.seqs; |
21、PostgreSQL 谁堵塞了谁(锁等待检测)- pg_blocking_pids
《PostgreSQL 谁堵塞了谁(锁等待检测)- pg_blocking_pids》
22、查询没有使用过的大于1MB的索引 top 10 (注意, PK、UK如果只是用于约束, 可能不会被统计计数,但是不能删掉)
1 |
select * from dba.top10notusedidx; |
23、查询没有使用过的大于1MB的表 top 10
1 |
select * from dba.top10notusedtab; |
24、查询热表top 10
1 |
select * from dba.top10hottab; |
25、查询大于1MB的冷表top 10
1 |
select * from dba.top10coldtab; |
26、查询热索引top 10
1 |
select * from dba.top10hotidx; |
27、查询大于1MB的冷索引top 10(注意, PK、UK如果只是用于约束, 可能不会被统计计数,但是不能删掉)
1 |
select * from dba.top10coldidx; |
28、查询数据库freeze风暴预测
1 2 3 4 5 |
select * from dba.v_freeze;
select * from dba.v_freeze_stat;
select * from dba.v_freeze_stat_detail; |
查询top 20的大表大freeze剩余年龄。
1 2 3 4 |
select * from dba.top20freezebigtable;
-- 结合dba.tps, 可以通过remain_ages_xid/dba.tps估算每个表还有多久会发生freeze. call dba.tps(); |
29、查询RO节点读与replay冲突次数, 建议高频恢复中的ro节点不要跑长sql。
1 |
select * from dba.ro_conflicts; |
30、DBA在RO 节点人为执行SQL前, 建议设置sql超时, 避免长时间跑 SQL, 导致不必要的replay延迟和 conflict cancel statement
1 2 |
set statement_timeout = '1s' ; set lock_timeout= '10ms' ; |
31、RO 节点的conflict容忍时间最长设置, 默认为5 min
1 2 3 4 5 |
show max_standby_streaming_delay ; max_standby_streaming_delay ----------------------------- 5min (1 row) |
32、清理数据库stat计数器
1 2 3 4 5 6 7 8 9 10 11 12 13 14 |
\df *.*reset* List of functions Schema | Name | Result data type | Argument data types | Type ------------+----------------------------------------+--------------------------+---------------------+------ pg_catalog | pg_replication_origin_session_reset | void | | func pg_catalog | pg_replication_origin_xact_reset | void | | func pg_catalog | pg_stat_get_bgwriter_stat_reset_time | timestamp with time zone | | func pg_catalog | pg_stat_get_db_stat_reset_time | timestamp with time zone | oid | func pg_catalog | pg_stat_reset | void | | func pg_catalog | pg_stat_reset_shared | void | text | func pg_catalog | pg_stat_reset_single_function_counters | void | oid | func pg_catalog | pg_stat_reset_single_table_counters | void | oid | func public | pg_stat_statements_reset | void | | func (9 rows ) |
33、在standby节点执行, 检查当前standby节点接收wal的速度
1 |
call dba.wal_receive_bw(); |
34、在standby节点执行, 检查当前standby节点replay wal的速度
1 |
call dba.wal_replay_bw(); |
35、wal文件使用、slot风险查看。
1 2 3 4 5 6 7 8 9 10 11 |
select * from dba.arch_undone;
select * from dba.arch_status;
select * from dba.walsize;
select * from dba.repslots;
select * from dba.wal_keep_size;
select * from dba.max_wal_size; |
36、长事务、prepared statement
1 |
select * from dba.long_snapshot; |
37、查询失效的索引。
1 |
select * from dba.invalid_index; |
参考
《PostgreSQL 实时健康监控 大屏 - 低频指标 - 珍藏级》
《PostgreSQL 实时健康监控 大屏 - 高频指标(服务器) - 珍藏级》
《PostgreSQL 实时健康监控 大屏 - 高频指标 - 珍藏级》
《PostgreSQL Freeze 风暴预测续 - 珍藏级SQL》
到此这篇关于PostgreSQL DBA最常用SQL的文章就介绍到这了,更多相关PostgreSQL DBA常用SQL内容请搜索服务器之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持服务器之家!
原文链接:https://www.cnblogs.com/88223100/archive/2022/10/17/The-most-commonly-used-SQL-for-PostgreSQL-DBAs.html
查看更多关于史上最全PostgreSQL DBA最常用SQL的详细内容...