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Μία μέθοδος για τη λήψη προφίλ φόρτου εργασίας και ιστορικού αναμονής στο PostgreSQL

Συνέχεια του άρθρου"Μια προσπάθεια δημιουργίας ενός αναλόγου ASH για την PostgreSQL ".

Το άρθρο θα εξετάσει και θα δείξει, χρησιμοποιώντας συγκεκριμένα ερωτήματα και παραδείγματα, ποιες χρήσιμες πληροφορίες μπορούν να ληφθούν χρησιμοποιώντας το ιστορικό της προβολής pg_stat_activity.

Προειδοποίηση.
Λόγω της καινοτομίας του θέματος και της ημιτελούς περιόδου δοκιμής, το άρθρο ενδέχεται να περιέχει σφάλματα. Η κριτική και τα σχόλια είναι ιδιαίτερα ευπρόσδεκτα και αναμενόμενα.

Εισαγωγή δεδομένων

pg_stat_statements ιστορικό υποβολής

pg_stat_history

CREATE TABLE pg_stat_history ( 
id SERIAL, 
snapshot_timestamp  timestamp without time zone, 
database_id integer,
dbid oid,
userid oid,
queryid bigint,
query text,
calls bigint, 
total_time double precision, 
min_time double precision, 
max_time double precision, 
mean_time double precision,
stddev_time double precision,
rows bigint,
shared_blks_hit bigint, 
shared_blks_read bigint, 
shared_blks_dirtied bigint, 
shared_blks_written bigint, 
local_blks_hit bigint, 
local_blks_read bigint,
local_blks_dirtied bigint, 
local_blks_written bigint, 
temp_blks_read bigint,
temp_blks_written bigint,
blk_read_time double precision, 
blk_write_time double precision, 
baseline_id integer );

Ο πίνακας συμπληρώνεται κάθε ώρα χρησιμοποιώντας dblink στη βάση δεδομένων προορισμού. Η πιο ενδιαφέρουσα και χρήσιμη στήλη στον πίνακα, φυσικά ερωτηματικά.

pg_stat_activity ιστορικό προβολής

archive_pg_stat_activity

CREATE TABLE archive_pg_stat_activity
(
  timepoint timestamp without time zone,
  datid             oid, 
  datname           name,
  pid               integer,
  usesysid          oid,
  usename           name,
  application_name  text,
  client_addr       inet,
  client_hostname   text,
  client_port       integer,
  backend_start     timestamp without time zone,
  xact_start        timestamp without time zone,
  query_start       timestamp without time zone,
  state_change      timestamp without time zone,
  wait_event_type   text,                     
  wait_event        text,                   
  state             text,                  
  backend_xid       xid,                 
  backend_xmin      xid,                
  query             text,               
  backend_type      text,
  queryid           bigint
);

Ο πίνακας είναι ένας πίνακας history_pg_stat_activity χωρισμένο ανά ώρα (Περισσότερες λεπτομέρειες εδώ - pg_stat_statements + pg_stat_activity + loq_query = pg_ash; και εδώ - Μια προσπάθεια δημιουργίας ενός αναλόγου του ASH για την PostgreSQL.)

Παραγωγή

ΧΡΟΝΟΣ CPU CLUST (ΣΥΣΤΗΜΑ + ΠΕΛΑΤΕΣ)

Αίτηση

WITH 
 t AS
 (
	SELECT 		
			date_trunc('second', timepoint)
	FROM 	activity_hist.archive_pg_stat_activity aa
	WHERE 	timepoint BETWEEN pg_stat_history_begin+(current_hour_diff * interval '1 hour') AND pg_stat_history_end+(current_hour_diff * interval '1 hour')  AND 
			( aa.wait_event_type IS NULL  ) AND
			aa.state = 'active'
 )
 SELECT count(*) 
 INTO cpu_total
 FROM t ;

Παράδειγμα

CLUSTER CPU TIME (SYSTEM + CLIENTS ) : 28:37:46

ΧΡΟΝΟΣ ΑΝΑΜΟΝΗΣ ΣΥΣΤΗΜΑΤΟΣ

Αίτηση

WITH 
 t AS
 (
	SELECT 		
			date_trunc('second', timepoint)
	FROM 	activity_hist.archive_pg_stat_activity aa
	WHERE 	timepoint BETWEEN pg_stat_history_begin+(current_hour_diff * interval '1 hour') AND pg_stat_history_end+(current_hour_diff * interval '1 hour')  AND 
			( aa.wait_event_type IS NOT NULL  ) AND
			aa.state = 'active'
 )
 SELECT count(*) 
 INTO cpu_total
 FROM t ;

Παράδειγμα

CLUSTER WAITINGS TIME : 30:12:49

Συνολικές τιμές pg_stat_statements

Αίτηση

 --TOTAL pg_stat
  SELECT 
    SUM(calls) AS calls, SUM(total_time)  AS total_time, SUM(rows) AS rows ,
	SUM(shared_blks_hit)  AS shared_blks_hit,SUM(shared_blks_read) AS shared_blks_read ,
	SUM(shared_blks_dirtied) AS shared_blks_dirtied,SUM(shared_blks_written) AS shared_blks_written , 
    SUM(local_blks_hit) AS local_blks_hit , SUM(local_blks_read) AS local_blks_read , 
	SUM(local_blks_dirtied) AS local_blks_dirtied , SUM(local_blks_written)  AS local_blks_written,
	SUM(temp_blks_read) AS temp_blks_read, SUM(temp_blks_written) temp_blks_written , 
	SUM(blk_read_time) AS blk_read_time , SUM(blk_write_time) AS blk_write_time
  INTO 
    pg_total_stat_history_rec
  FROM 
    pg_stat_history
  WHERE 
 	snapshot_timestamp BETWEEN pg_stat_history_begin AND pg_stat_history_end AND 
	queryid IS NULL;

SQL DBTIME - συνολικός χρόνος εκτέλεσης ερωτήματος

Αίτηση

dbtime_total = interval '1 millisecond' * pg_total_stat_history_rec.total_time ;

Παράδειγμα

SQL DBTIME : 136:49:36

SQL CPU TIME - Χρόνος CPU που δαπανάται για την εκτέλεση ερωτημάτων

Αίτηση

WITH 
 t AS
 (
	SELECT 		
			date_trunc('second', timepoint)
	FROM 	activity_hist.archive_pg_stat_activity aa
	WHERE 	timepoint BETWEEN pg_stat_history_begin+(current_hour_diff * interval '1 hour') AND pg_stat_history_end+(current_hour_diff * interval '1 hour')  AND 
			( aa.wait_event_type IS NULL  ) AND
			backend_type = 'client backend' AND 
			aa.state = 'active'
 )
 SELECT count(*) 
 INTO cpu_total
 FROM t ;

Παράδειγμα

SQL CPU TIME : 27:40:15

SQL WAITINGS TIME - συνολικός χρόνος αναμονής για ερωτήματα

Αίτηση

WITH 
 t AS
 (
	SELECT 		
			date_trunc('second', timepoint)
	FROM 	activity_hist.archive_pg_stat_activity aa
	WHERE 	timepoint BETWEEN pg_stat_history_begin+(current_hour_diff * interval '1 hour') AND pg_stat_history_end+(current_hour_diff * interval '1 hour')  AND 
			( aa.wait_event_type IS NOT NULL  ) AND
			aa.state = 'active' AND 
		backend_type = 'client backend'
 )
 SELECT count(*) 
 INTO waiting_total
 FROM t ;

Παράδειγμα

SQL WAITINGS TIME : 30:04:09

Τα ακόλουθα ερωτήματα είναι ασήμαντα και οι λεπτομέρειες υλοποίησης παραλείπονται για εξοικονόμηση χώρου:

Παράδειγμα

| SQL IOTIME : 19:44:50
| SQL READ TIME : 19:44:32
| SQL WRITE TIME : 00:00:17
|
| SQL CALLS : 12188248
-------------------------------------------------------------
| SQL SHARED BLOCKS READS : 7997039120
| SQL SHARED BLOCKS HITS : 8868286092
| SQL SHARED BLOCKS HITS/READS % : 110.89
| SQL SHARED BLOCKS DIRTED : 419945
| SQL SHARED BLOCKS WRITTEN : 19857
|
| SQL TEMPORARY BLOCKS READS : 7836169
| SQL TEMPORARY BLOCKS WRITTEN : 10683938

Ας περάσουμε στην πιο ενδιαφέρουσα ενότητα

ΑΝΑΜΟΝΗ ΣΤΑΤΙΚΗ

TOP 10 ΑΝΑΜΟΝΕΣ ΑΝΑ ΣΥΝΟΛΙΚΟ ΧΡΟΝΟ ΑΝΑΜΟΝΗΣ ΓΙΑ ΔΙΑΔΙΚΑΣΙΕΣ ΠΕΛΑΤΩΝ

Αίτηση

SELECT 
  wait_event_type , wait_event ,
  get_system_waiting_duration( wait_event_type , wait_event ,pg_stat_history_begin+(current_hour_diff * interval '1 hour') ,pg_stat_history_end+(current_hour_diff * interval '1 hour') ) as duration 
FROM
  activity_hist.archive_pg_stat_activity aa
WHERE 
  timepoint BETWEEN pg_stat_history_begin+(current_hour_diff * interval '1 hour') AND pg_stat_history_end+(current_hour_diff * interval '1 hour') AND backend_type != 'client backend' AND wait_event_type IS NOT NULL 
GROUP BY 
  wait_event_type, wait_event
ORDER BY 3 DESC
LIMIT 10

Παράδειγμα

+------------------------------------------------- ------------------------------------ | 10 ΚΟΡΥΦΑΙΕΣ ΑΝΑΜΟΝΕΣ ΑΝΑ ΣΥΝΟΛΙΚΟ ΧΡΟΝΟ ΑΝΑΜΟΝΗΣ ΓΙΑ ΔΙΑΔΙΚΑΣΙΕΣ ΣΥΣΤΗΜΑΤΟΣ +-----+-----------------------------+--- ---------------------------------------- | #| wait_event_type| αναμονή_γεγονός| διάρκεια +-----+---------------------------+----------- -------+---------- | 1| Δραστηριότητα| LogicalLauncherMain| 10:43:28 | 2| Δραστηριότητα| AutoVacuumMain| 10:42:49 | 3| Δραστηριότητα| WalWriterMain| 10:28:53 | 4| Δραστηριότητα| CheckpointerMain| 10:23:50 | 5| Δραστηριότητα| BgWriterMain| 09:11:59 | 6| Δραστηριότητα| BgWriterHibernate| 01:37:46 | 7| IO| BufFileWrite| 00:02:35 | 8| LWLock| buffer_mapping| 00:01:54 | 9| IO| DataFileRead| 00:01:23 | 10| IO| WALWrite| 00:00:59 +-----+--------------------------------------- -------------+-----------

TOP 10 ΑΝΑΜΟΝΕΣ ΑΝΑ ΣΥΝΟΛΙΚΟ ΧΡΟΝΟ ΑΝΑΜΟΝΗΣ ΓΙΑ ΔΙΑΔΙΚΑΣΙΕΣ ΠΕΛΑΤΩΝ

Αίτηση

SELECT 
  wait_event_type , wait_event ,
  get_clients_waiting_duration( wait_event_type , wait_event , pg_stat_history_begin+(current_hour_diff * interval '1 hour') , pg_stat_history_end+(current_hour_diff * interval '1 hour') ) as duration
FROM 
  activity_hist.archive_pg_stat_activity aa
WHERE 
  timepoint BETWEEN pg_stat_history_begin+(current_hour_diff * interval '1 hour') AND pg_stat_history_end+(current_hour_diff * interval '1 hour') AND backend_type = 'client backend' AND wait_event_type IS NOT NULL 
GROUP BY wait_event_type, wait_event
ORDER BY 3 DESC
LIMIT 10

Παράδειγμα

+----------+-------------------------------------- --- ---------+----------+----------- | #| τύπος_συμβάντος_αναμονής| αναμονή_γεγονός| διάρκεια| % dbtime +-----+------------------------------------------- ----------+----------+----------- | 1| Κλειδαριά| συναλλαγής| 08:16:47| 6.05 | 2| IO| DataFileRead| 06:13:41| 4.55 | 3| Timeout| PgSleep| 02:53:21| 2.11 | 4| LWLock| buffer_mapping| 00:40:42| 0.5 | 5| LWLock| buffer_io| 00:17:17| 0.21 | 6| IO| BufFileWrite| 00:01:34| 0.02 | 7| Κλειδαριά| πλειάδα| 00:01:32| 0.02 | 8| Πελάτης| ClientRead| 00:01:19| 0.02 | 9| IO| BufFileRead| 00:00:37| 0.01 | 10| LWLock| buffer_content| 00:00:08| 0 +-----+----------------------------------------- -------+-----------------------

ΤΥΠΟΙ ΑΝΑΜΟΝΗΣ ΑΝΑ ΣΥΝΟΛΙΚΟ ΧΡΟΝΟ ΑΝΑΜΟΝΗΣ, ΓΙΑ ΔΙΑΔΙΚΑΣΙΕΣ ΣΥΣΤΗΜΑΤΟΣ

Αίτηση

SELECT 
  wait_event_type ,
  get_system_waiting_type_duration( wait_event_type , pg_stat_history_begin+(current_hour_diff * interval '1 hour') , pg_stat_history_end+(current_hour_diff * interval '1 hour') ) as duration
FROM
  activity_hist.archive_pg_stat_activity aa
WHERE 
  timepoint BETWEEN pg_stat_history_begin+(current_hour_diff * interval '1 hour') AND pg_stat_history_end+(current_hour_diff * interval '1 hour') AND  backend_type != 'client backend' AND wait_event_type IS NOT NULL 
GROUP BY wait_event_type
ORDER BY 2 DESC

Παράδειγμα

+----------+-------------------------------------- --- -------- | #| τύπος_συμβάντος_αναμονής| διάρκεια +-----+---------------------------+----------- ------- | 1| Δραστηριότητα| 53:08:45 | 2| IO| 00:06:24 | 3| LWLock| 00:03:02 +-----+--------------------------------------- --------------

ΤΥΠΟΙ ΑΝΑΜΟΝΗΣ ΑΝΑ ΣΥΝΟΛΙΚΟ ΧΡΟΝΟ ΑΝΑΜΟΝΗΣ, ΓΙΑ ΔΙΑΔΙΚΑΣΙΕΣ ΠΕΛΑΤΩΝ

Αίτηση

SELECT 
  wait_event_type ,
  get_clients_waiting_type_duration( wait_event_type , pg_stat_history_begin+(current_hour_diff * interval '1 hour') , pg_stat_history_end+(current_hour_diff * interval '1 hour') ) as duration
FROM
  activity_hist.archive_pg_stat_activity aa
WHERE 
  timepoint BETWEEN pg_stat_history_begin+(current_hour_diff * interval '1 hour') AND pg_stat_history_end+(current_hour_diff * interval '1 hour') AND backend_type = 'client backend' AND wait_event_type IS NOT NULL 
GROUP BY wait_event_type
ORDER BY 2 DESC

Παράδειγμα

+----------+-------------------------------------- --- ---------+---------- | #| τύπος_συμβάντος_αναμονής| διάρκεια| % dbtime +-----+------------------------------------------- ----------+--------------------- | 1| Κλειδαριά| 08:18:19| 6.07 | 2| IO| 06:16:01| 4.58 | 3| Timeout| 02:53:21| 2.11 | 4| LWLock| 00:58:12| 0.71 | 5| Πελάτης| 00:01:19| 0.02 | 6| IPC| 00:00:04| 0 +-----+----------------------------+------------ -------+---------------------

Διάρκειες αναμονής για διαδικασίες συστήματος και μεμονωμένα αιτήματα.

ΑΝΑΜΟΝΗ ΓΙΑ ΔΙΑΔΙΚΑΣΙΕΣ ΣΥΣΤΗΜΑΤΟΣ

Αίτηση

SELECT 
  backend_type , datname , wait_event_type , wait_event , get_backend_type_waiting_duration( backend_type , wait_event_type , wait_event , pg_stat_history_begin+(current_hour_diff * interval '1 hour') , pg_stat_history_end+(current_hour_diff * interval '1 hour') ) as duration 
FROM 
  activity_hist.archive_pg_stat_activity aa
WHERE 
  timepoint BETWEEN pg_stat_history_begin+(current_hour_diff * interval '1 hour') AND pg_stat_history_end+(current_hour_diff * interval '1 hour') AND backend_type != 'client backend' AND wait_event_type IS NOT NULL 
GROUP BY backend_type , datname , wait_event_type , wait_event
ORDER BY 5 DESC

Παράδειγμα

+-----+-----------------------------+----------+--------------------+----------------------+--------------------
|    #|                 backend_type|    dbname|     wait_event_type|            wait_event|            duration
+-----+-----------------------------+----------+--------------------+----------------------+--------------------
|    1| logical replication launcher|          |            Activity|   LogicalLauncherMain|            10:43:28
|    2|          autovacuum launcher|          |            Activity|        AutoVacuumMain|            10:42:49
|    3|                    walwriter|          |            Activity|         WalWriterMain|            10:28:53
|    4|                 checkpointer|          |            Activity|      CheckpointerMain|            10:23:50
|    5|            background writer|          |            Activity|          BgWriterMain|            09:11:59
|    6|            background writer|          |            Activity|     BgWriterHibernate|            01:37:46
|    7|              parallel worker|      tdb1|                  IO|          BufFileWrite|            00:02:35
|    8|              parallel worker|      tdb1|              LWLock|        buffer_mapping|            00:01:41
|    9|              parallel worker|      tdb1|                  IO|          DataFileRead|            00:01:22
|   10|              parallel worker|      tdb1|                  IO|           BufFileRead|            00:00:59
|   11|                    walwriter|          |                  IO|              WALWrite|            00:00:57
|   12|              parallel worker|      tdb1|              LWLock|             buffer_io|            00:00:47
|   13|            autovacuum worker|      tdb1|              LWLock|        buffer_mapping|            00:00:13
|   14|            background writer|          |                  IO|         DataFileWrite|            00:00:12
|   15|                 checkpointer|          |                  IO|         DataFileWrite|            00:00:11
|   16|                    walwriter|          |              LWLock|          WALWriteLock|            00:00:09
|   17|                 checkpointer|          |              LWLock|          WALWriteLock|            00:00:06
|   18|            background writer|          |              LWLock|          WALWriteLock|            00:00:06
|   19|                    walwriter|          |                  IO|          WALInitWrite|            00:00:02
|   20|            autovacuum worker|      tdb1|              LWLock|          WALWriteLock|            00:00:02
|   21|                    walwriter|          |                  IO|           WALInitSync|            00:00:02
|   22|            autovacuum worker|      tdb1|                  IO|          DataFileRead|            00:00:01
|   23|                 checkpointer|          |                  IO| ControlFileSyncUpdate|            00:00:01
|   24|            background writer|          |                  IO|              WALWrite|            00:00:01
|   25|            background writer|          |                  IO|         DataFileFlush|            00:00:01
|   26|                 checkpointer|          |                  IO|         SLRUFlushSync|            00:00:01
|   27|            autovacuum worker|      tdb1|                  IO|              WALWrite|            00:00:01
|   28|                 checkpointer|          |                  IO|          DataFileSync|            00:00:01
+-----+-----------------------------+----------+--------------------+----------------------+--------------------

WAITINGS FOR SQL - αναμένει μεμονωμένα ερωτήματα ανά queryid

Αίτηση

SELECT 
queryid , datname , wait_event_type , wait_event , get_query_waiting_duration( queryid ,  wait_event_type , wait_event , pg_stat_history_begin+(current_hour_diff * interval '1 hour') , pg_stat_history_end+(current_hour_diff * interval '1 hour') ) as duration 
FROM 
  activity_hist.archive_pg_stat_activity aa
WHERE 
  timepoint BETWEEN pg_stat_history_begin+(current_hour_diff * interval '1 hour') AND pg_stat_history_end+(current_hour_diff * interval '1 hour') AND backend_type = 'client backend' AND wait_event_type IS NOT NULL AND queryid IS NOT NULL 
GROUP BY queryid , datname , wait_event_type , wait_event
ORDER BY 1 , 5 DESC

Παράδειγμα

+-----+-------------------------+----------+--------------------+--------------------+--------------------+--------------------
|    #|                  queryid|    dbname|     wait_event_type|          wait_event|            waitings|               total
|     |                         |          |                    |                    |            duration|            duration
+-----+-------------------------+----------+--------------------+--------------------+--------------------+--------------------
|    1|     -8247416849404883188|      tdb1|              Client|          ClientRead|            00:00:02|
|    2|     -6572922443698419129|      tdb1|              Client|          ClientRead|            00:00:05|
|    3|     -6572922443698419129|      tdb1|                  IO|        DataFileRead|            00:00:01|
|    4|     -5917408132400665328|      tdb1|              Client|          ClientRead|            00:00:04|
|    5|     -4091009262735781873|      tdb1|              Client|          ClientRead|            00:00:03|
|    6|     -1473395109729441239|      tdb1|              Client|          ClientRead|            00:00:01|
|    7|        28942442626229688|      tdb1|                  IO|        BufFileWrite|            00:01:34|            00:46:06
|    8|        28942442626229688|      tdb1|              LWLock|      buffer_mapping|            00:01:05|            00:46:06
|    9|        28942442626229688|      tdb1|                  IO|        DataFileRead|            00:00:44|            00:46:06
|   10|        28942442626229688|      tdb1|                  IO|         BufFileRead|            00:00:37|            00:46:06
|   11|        28942442626229688|      tdb1|              LWLock|           buffer_io|            00:00:35|            00:46:06
|   12|        28942442626229688|      tdb1|              Client|          ClientRead|            00:00:05|            00:46:06
|   13|        28942442626229688|      tdb1|                 IPC| MessageQueueReceive|            00:00:03|            00:46:06
|   14|        28942442626229688|      tdb1|                 IPC|    BgWorkerShutdown|            00:00:01|            00:46:06
|   15|       389015618226997618|      tdb1|                Lock|       transactionid|            03:55:09|            04:14:15
|   16|       389015618226997618|      tdb1|                  IO|        DataFileRead|            03:23:09|            04:14:15
|   17|       389015618226997618|      tdb1|              LWLock|      buffer_mapping|            00:12:09|            04:14:15
|   18|       389015618226997618|      tdb1|              LWLock|           buffer_io|            00:10:18|            04:14:15
|   19|       389015618226997618|      tdb1|                Lock|               tuple|            00:00:35|            04:14:15
|   20|       389015618226997618|      tdb1|              LWLock|        WALWriteLock|            00:00:02|            04:14:15
|   21|       389015618226997618|      tdb1|                  IO|       DataFileWrite|            00:00:01|            04:14:15
|   22|       389015618226997618|      tdb1|              LWLock|        SyncScanLock|            00:00:01|            04:14:15
|   23|       389015618226997618|      tdb1|              Client|          ClientRead|            00:00:01|            04:14:15
|   24|       734234407411547467|      tdb1|              Client|          ClientRead|            00:00:11|
|   25|       734234407411547467|      tdb1|              LWLock|      buffer_mapping|            00:00:05|
|   26|       734234407411547467|      tdb1|                  IO|        DataFileRead|            00:00:02|
|   27|      1237430309438971376|      tdb1|              LWLock|      buffer_mapping|            00:02:18|            02:45:40
|   28|      1237430309438971376|      tdb1|                  IO|        DataFileRead|            00:00:27|            02:45:40
|   29|      1237430309438971376|      tdb1|              Client|          ClientRead|            00:00:02|            02:45:40
|   30|      2404820632950544954|      tdb1|              Client|          ClientRead|            00:00:01|
|   31|      2515308626622579467|      tdb1|              Client|          ClientRead|            00:00:02|
|   32|      4710212362688288619|      tdb1|              LWLock|      buffer_mapping|            00:03:08|            02:18:21
|   33|      4710212362688288619|      tdb1|                  IO|        DataFileRead|            00:00:22|            02:18:21
|   34|      4710212362688288619|      tdb1|              Client|          ClientRead|            00:00:06|            02:18:21
|   35|      4710212362688288619|      tdb1|              LWLock|           buffer_io|            00:00:02|            02:18:21
|   36|      9150846928388977274|      tdb1|                  IO|        DataFileRead|            00:01:19|
|   37|      9150846928388977274|      tdb1|              LWLock|      buffer_mapping|            00:00:34|
|   38|      9150846928388977274|      tdb1|              Client|          ClientRead|            00:00:10|
|   39|      9150846928388977274|      tdb1|              LWLock|           buffer_io|            00:00:01|
+-----+-------------------------+----------+--------------------+--------------------+--------------------+--------------------

CLIENT SQL STATICTICS - ΚΟΡΥΦΑΙΑ ερωτήματα

Τα αιτήματα για παραλαβή είναι και πάλι ασήμαντα και δεν δίνονται για εξοικονόμηση χώρου.

παραδείγματα

+------------------------------------------------------------------------------------
| CLIENT SQL ordered by Elapsed Time
+--------------------+----------+----------+----------+----------+----------+--------------------
|        elapsed time|     calls|  % dbtime|     % CPU|      % IO|    dbname|             queryid
+--------------------+----------+----------+----------+----------+----------+--------------------
|            04:14:15|        19|       3.1|     10.83|     11.52|      tdb1|  389015618226997618
|            02:45:40|       746|      2.02|      4.23|      0.08|      tdb1| 1237430309438971376
|            02:18:21|       749|      1.69|      3.39|       0.1|      tdb1| 4710212362688288619
|            00:46:06|       375|      0.56|      0.94|      0.41|      tdb1|   28942442626229688
+--------------------+----------+----------+----------+----------+----------+--------------------
| CLIENT SQL ordered by CPU Time
+--------------------+----------+----------+----------+----------+----------+----------+--------------------
|            cpu time|     calls|  % dbtime|total_time|     % CPU|      % IO|    dbname|             queryid
+--------------------+----------+----------+----------+----------+----------+----------+--------------------
|            02:59:49|        19|       3.1|  04:14:15|     10.83|     11.52|      tdb1|  389015618226997618
|            01:10:12|       746|      2.02|  02:45:40|      4.23|      0.08|      tdb1| 1237430309438971376
|            00:56:15|       749|      1.69|  02:18:21|      3.39|       0.1|      tdb1| 4710212362688288619
|            00:15:35|       375|      0.56|  00:46:06|      0.94|      0.41|      tdb1|   28942442626229688
+--------------------+----------+----------+----------+----------+----------+----------+--------------------
| CLIENT SQL ordered by User I/O Wait Time
+--------------------+----------+----------+----------+----------+----------+----------+--------------------
|        io_wait time|     calls|  % dbtime|total_time|     % CPU|      % IO|    dbname|             queryid
+--------------------+----------+----------+----------+----------+----------+----------+--------------------
|            03:23:10|        19|       3.1|  04:14:15|     10.83|     11.52|      tdb1|  389015618226997618
|            00:02:54|       375|      0.56|  00:46:06|      0.94|      0.41|      tdb1|   28942442626229688
|            00:00:27|       746|      2.02|  02:45:40|      4.23|      0.08|      tdb1| 1237430309438971376
|            00:00:22|       749|      1.69|  02:18:21|      3.39|       0.1|      tdb1| 4710212362688288619
+--------------------+----------+----------+----------+----------+----------+----------+--------------------
| CLIENT SQL ordered by Shared Buffers Reads
+--------------------+----------+----------+----------+----------+----------+----------+--------------------
|       buffers reads|     calls|  % dbtime|total_time|     % CPU|      % IO|    dbname|             queryid
+--------------------+----------+----------+----------+----------+----------+----------+--------------------
|          1056388566|        19|       3.1|  04:14:15|     10.83|     11.52|      tdb1|  389015618226997618
|            11709251|       375|      0.56|  00:46:06|      0.94|      0.41|      tdb1|   28942442626229688
|             3439004|       746|      2.02|  02:45:40|      4.23|      0.08|      tdb1| 1237430309438971376
|             3373330|       749|      1.69|  02:18:21|      3.39|       0.1|      tdb1| 4710212362688288619
+--------------------+----------+----------+----------+----------+----------+----------+--------------------
| CLIENT SQL ordered by Disk Reads Time
+--------------------+----------+----------+----------+----------+----------+----------+--------------------
|           read time|     calls|  % dbtime|total_time|     % CPU|      % IO|    dbname|             queryid
+--------------------+----------+----------+----------+----------+----------+----------+--------------------
|            02:16:30|        19|       3.1|  04:14:15|     10.83|     11.52|      tdb1|  389015618226997618
|            00:04:50|       375|      0.56|  00:46:06|      0.94|      0.41|      tdb1|   28942442626229688
|            00:01:10|       749|      1.69|  02:18:21|      3.39|       0.1|      tdb1| 4710212362688288619
|            00:00:57|       746|      2.02|  02:45:40|      4.23|      0.08|      tdb1| 1237430309438971376
+--------------------+----------+----------+----------+----------+----------+----------+--------------------
| CLIENT SQL ordered by Executions
+--------------------+----------+----------+----------+----------+----------+----------+--------------------
|               calls|      rows|  % dbtime|total_time|     % CPU|      % IO|    dbname|             queryid
+--------------------+----------+----------+----------+----------+----------+----------+--------------------
|                 749|       749|      1.69|  02:18:21|      3.39|       0.1|      tdb1| 4710212362688288619
|                 746|       746|      2.02|  02:45:40|      4.23|      0.08|      tdb1| 1237430309438971376
|                 375|         0|      0.56|  00:46:06|      0.94|      0.41|      tdb1|   28942442626229688
|                  19|        19|       3.1|  04:14:15|     10.83|     11.52|      tdb1|  389015618226997618
+--------------------+----------+----------+----------+----------+----------+----------+--------------------

Σύνολο

Χρησιμοποιώντας τα ερωτήματα που υποβλήθηκαν και τις αναφορές που προκύπτουν, μπορείτε να αποκτήσετε μια πιο ολοκληρωμένη εικόνα για την ανάλυση και την επίλυση προβλημάτων υποβάθμισης της απόδοσης για μεμονωμένα ερωτήματα και ολόκληρο το σύμπλεγμα συνολικά.

Ανάπτυξη

Μέχρι στιγμής τα αναπτυξιακά σχέδια έχουν ως εξής:

  • Συμπλήρωμα αναφοράς με ιστορικό αποκλεισμού. Τα αιτήματα ελέγχονται και θα υποβληθούν σύντομα.
  • Χρησιμοποιήστε την επέκταση TimescaleDB για να αποθηκεύσετε το ιστορικό pg_stat_activity και pg_locks.
  • Προετοιμάστε μια λύση συσκευασίας στο github για μαζική ανάπτυξη σε βάσεις παραγωγής.

Για να συνεχιστεί ...

Πηγή: www.habr.com

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