Daŭrigo de la artikolo "
La artikolo ekzamenos kaj montros, uzante specifajn demandojn kaj ekzemplojn, kiajn utilajn informojn oni povas akiri uzante la historion de la vido pg_locks.
Averto.
Pro la noveco de la temo kaj la nefinita testa periodo, la artikolo povas enhavi erarojn. Kritiko kaj komentoj estas forte bonvenataj kaj atendataj.
Eniga datumoj
Historio de pg_locks reprezentado
arĥivo_ŝlosado
CREATE TABLE archive_locking
( timepoint timestamp without time zone ,
locktype text ,
relation oid ,
mode text ,
tid xid ,
vtid text ,
pid integer ,
blocking_pids integer[] ,
granted boolean ,
queryid bigint
);
Esence, la tablo estas simila al la tablo archive_pg_stat_activity, priskribita pli detale ĉi tie -
Por plenigi kolumnon queryid funkcio estas uzata
ĝisdatigo_historio_ŝlosado_per_queryid
--update_history_locking_by_queryid.sql
CREATE OR REPLACE FUNCTION update_history_locking_by_queryid() RETURNS boolean AS $$
DECLARE
result boolean ;
current_minute double precision ;
start_minute integer ;
finish_minute integer ;
start_period timestamp without time zone ;
finish_period timestamp without time zone ;
lock_rec record ;
endpoint_rec record ;
current_hour_diff double precision ;
BEGIN
RAISE NOTICE '***update_history_locking_by_queryid';
result = TRUE ;
current_minute = extract ( minute from now() );
SELECT * FROM endpoint WHERE is_need_monitoring
INTO endpoint_rec ;
current_hour_diff = endpoint_rec.hour_diff ;
IF current_minute < 5
THEN
RAISE NOTICE 'Current time is less than 5 minute.';
start_period = date_trunc('hour',now()) + (current_hour_diff * interval '1 hour');
finish_period = start_period - interval '5 minute' ;
ELSE
finish_minute = extract ( minute from now() ) / 5 ;
start_minute = finish_minute - 1 ;
start_period = date_trunc('hour',now()) + interval '1 minute'*start_minute*5+(current_hour_diff * interval '1 hour');
finish_period = date_trunc('hour',now()) + interval '1 minute'*finish_minute*5+(current_hour_diff * interval '1 hour') ;
END IF ;
RAISE NOTICE 'start_period = %', start_period;
RAISE NOTICE 'finish_period = %', finish_period;
FOR lock_rec IN
WITH act_queryid AS
(
SELECT
pid ,
timepoint ,
query_start AS started ,
MAX(timepoint) OVER (PARTITION BY pid , query_start ) AS finished ,
queryid
FROM
activity_hist.history_pg_stat_activity
WHERE
timepoint BETWEEN start_period and
finish_period
GROUP BY
pid ,
timepoint ,
query_start ,
queryid
),
lock_pids AS
(
SELECT
hl.pid ,
hl.locktype ,
hl.mode ,
hl.timepoint ,
MIN ( timepoint ) OVER (PARTITION BY pid , locktype ,mode ) as started
FROM
activity_hist.history_locking hl
WHERE
hl.timepoint between start_period and
finish_period
GROUP BY
hl.pid ,
hl.locktype ,
hl.mode ,
hl.timepoint
)
SELECT
lp.pid ,
lp.locktype ,
lp.mode ,
lp.timepoint ,
aq.queryid
FROM lock_pids lp LEFT OUTER JOIN act_queryid aq ON ( lp.pid = aq.pid AND lp.started BETWEEN aq.started AND aq.finished )
WHERE aq.queryid IS NOT NULL
GROUP BY
lp.pid ,
lp.locktype ,
lp.mode ,
lp.timepoint ,
aq.queryid
LOOP
UPDATE activity_hist.history_locking SET queryid = lock_rec.queryid
WHERE pid = lock_rec.pid AND locktype = lock_rec.locktype AND mode = lock_rec.mode AND timepoint = lock_rec.timepoint ;
END LOOP;
RETURN result ;
END
$$ LANGUAGE plpgsql;
Klarigo: la valoro de la queryid-kolumno estas ĝisdatigita en la history_locking-tabelo, kaj tiam kiam nova sekcio estas kreita por la archive_locking-tabelo, la valoro estos konservita en la historiaj valoroj.
Eligo
Ĝeneralaj informoj pri procezoj ĝenerale.
ATENDAS SERUROJ PER SERRUTIPOJ
Peto
WITH
t AS
(
SELECT
locktype ,
mode ,
count(*) as total
FROM
activity_hist.archive_locking
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
NOT granted
GROUP BY
locktype ,
mode
)
SELECT
locktype ,
mode ,
total * interval '1 second' as duration
FROM t
ORDER BY 3 DESC
Ekzemplo:
| ATENDAS SERUROJ PER SERRUTIPOJ +-----------+---------------------- --------+ ------------------- | serurotipo| reĝimo| daŭro +--------------------+-------------------------- --+-------------------- | transakciid| ShareLock| 19:39:26 | opo| AccessExclusiveLock| 00:03:35 +-------------------+----------------------- - -------+----------
PRENOJ DE SERUROJ PER SERRUTIPOJ
Peto
WITH
t AS
(
SELECT
locktype ,
mode ,
count(*) as total
FROM
activity_hist.archive_locking
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
granted
GROUP BY
locktype ,
mode
)
SELECT
locktype ,
mode ,
total * interval '1 second' as duration
FROM t
ORDER BY 3 DESC
Ekzemplo:
| PRENOJ DE SERUROJ PER SERRUTIPOJ +--------------------+----------------------- --------+------------------- | serurotipo| reĝimo| daŭro +--------------------+-------------------------- --+-------------------- | rilato| RowExclusiveLock| 51:11:10 | virtualxid| Ekskluziva Ŝlosilo| 48:10:43 | transakciid| Ekskluziva Ŝlosilo| 44:24:53 | rilato| AccessShareLock| 20:06:13 | opo| AccessExclusiveLock| 17:58:47 | opo| Ekskluziva Ŝlosilo| 01:40:41 | rilato| ShareUpdateExclusiveLock| 00:26:41 | objekto| RowExclusiveLock| 00:00:01 | transakciid| ShareLock| 00:00:01 | etendi| Ekskluziva Ŝlosilo| 00:00:01 +-------------------+----------------------- - -------+----------
Detalaj informoj pri specifaj queryid-petoj
ATENDAS SERRUĴOJ PER SERRUTIPOJ PER QUERYID
Peto
WITH
lt AS
(
SELECT
pid ,
locktype ,
mode ,
timepoint ,
queryid ,
blocking_pids ,
MIN ( timepoint ) OVER (PARTITION BY pid , locktype ,mode ) as started
FROM
activity_hist.archive_locking
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
NOT granted AND
queryid IS NOT NULL
GROUP BY
pid ,
locktype ,
mode ,
timepoint ,
queryid ,
blocking_pids
)
SELECT
lt.pid ,
lt.locktype ,
lt.mode ,
lt.started ,
lt.queryid ,
lt.blocking_pids ,
COUNT(*) * interval '1 second' as duration
FROM lt
GROUP BY
lt.pid ,
lt.locktype ,
lt.mode ,
lt.started ,
lt.queryid ,
lt.blocking_pids
ORDER BY 4
Ekzemplo:
| ATENDAS SERUROJ PER SERRUTIPOJ PER QUERYID +----------+----------+----- ---------------- +----------------------------+--- ----------------- -+--------------------+----------- ---------- | pid| serurotipo| reĝimo| komencis| queryid| blokado_pidoj| daŭro +----------+------------------------+----------- ---------+-----------------------------+--------- -----------+--------------------+----------------- --- | 11288| transakciid| ShareLock| 2019-09-17 10:00:00.302936| 389015618226997618| {11092}| 00:03:34 | 11626| transakciid| ShareLock| 2019-09-17 10:00:21.380921| 389015618226997618| {12380}| 00:00:29 | 11626| transakciid| ShareLock| 2019-09-17 10:00:21.380921| 389015618226997618| {11092}| 00:03:25 | 11626| transakciid| ShareLock| 2019-09-17 10:00:21.380921| 389015618226997618| {12213}| 00:01:55 | 11626| transakciid| ShareLock| 2019-09-17 10:00:21.380921| 389015618226997618| {12751}| 00:00:01 | 11629| transakciid| ShareLock| 2019-09-17 10:00:24.331935| 389015618226997618| {11092}| 00:03:22 | 11629| transakciid| ShareLock| 2019-09-17 10:00:24.331935| 389015618226997618| {12007}| 00:00:01 | 12007| transakciid| ShareLock| 2019-09-17 10:05:03.327933| 389015618226997618| {11629}| 00:00:13 | 12007| transakciid| ShareLock| 2019-09-17 10:05:03.327933| 389015618226997618| {11092}| 00:01:10 | 12007| transakciid| ShareLock| 2019-09-17 10:05:03.327933| 389015618226997618| {11288}| 00:00:05 | 12213| transakciid| ShareLock| 2019-09-17 10:06:07.328019| 389015618226997618| {12007}| 00:00:10
PRI SERUROJ PER SERRUTIPOJ PER QUERYID
Peto
WITH
lt AS
(
SELECT
pid ,
locktype ,
mode ,
timepoint ,
queryid ,
blocking_pids ,
MIN ( timepoint ) OVER (PARTITION BY pid , locktype ,mode ) as started
FROM
activity_hist.archive_locking
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
granted AND
queryid IS NOT NULL
GROUP BY
pid ,
locktype ,
mode ,
timepoint ,
queryid ,
blocking_pids
)
SELECT
lt.pid ,
lt.locktype ,
lt.mode ,
lt.started ,
lt.queryid ,
lt.blocking_pids ,
COUNT(*) * interval '1 second' as duration
FROM lt
GROUP BY
lt.pid ,
lt.locktype ,
lt.mode ,
lt.started ,
lt.queryid ,
lt.blocking_pids
ORDER BY 4
Ekzemplo:
| PRENO DE SERUROJ PER SERRUTIPOJ PER QUERYID +----------+----------+------ --------------+ ----------------------------+---- ----------------+ --------------------+------------ -------- | pid| serurotipo| reĝimo| komencis| queryid| blokado_pidoj| daŭro +----------+------------------------+----------- ---------+-----------------------------+--------- -----------+--------------------+----------------- --- | 11288| rilato| RowExclusiveLock| 2019-09-17 10:00:00.302936| 389015618226997618| {11092}| 00:03:34 | 11092| transakciid| Ekskluziva Ŝlosilo| 2019-09-17 10:00:00.302936| 389015618226997618| {}| 00:03:34 | 11288| rilato| RowExclusiveLock| 2019-09-17 10:00:00.302936| 389015618226997618| {}| 00:00:10 | 11092| rilato| RowExclusiveLock| 2019-09-17 10:00:00.302936| 389015618226997618| {}| 00:03:34 | 11092| virtualxid| Ekskluziva Ŝlosilo| 2019-09-17 10:00:00.302936| 389015618226997618| {}| 00:03:34 | 11288| virtualxid| Ekskluziva Ŝlosilo| 2019-09-17 10:00:00.302936| 389015618226997618| {11092}| 00:03:34 | 11288| transakciid| Ekskluziva Ŝlosilo| 2019-09-17 10:00:00.302936| 389015618226997618| {11092}| 00:03:34 | 11288| opo| AccessExclusiveLock| 2019-09-17 10:00:00.302936| 389015618226997618| {11092}| 00:03:34
Uzante ŝlosilhistorion por analizi agadojn okazaĵojn.
- Peto kun queryid=389015618226997618 efektivigita de procezo kun pid=11288 atendis blokadon ekde 2019-09-17 10:00:00 dum 3 minutoj.
- La seruro estis tenita per procezo kun pid=11092
- Procezo kun pid=11092 plenumanta peton kun queryid=389015618226997618 ekde 2019-09-17 10:00:00 tenis la seruron dum 3 minutoj.
La rezulto
Nun, mi esperas, komenciĝos la plej interesa kaj utila parto - kolekti statistikojn kaj analizi kazojn pri la historio de atendoj kaj blokadoj.
Estonte, mi volas kredi, ni ricevos aron da kelkaj notoj (similaj al la metaligo de Oracle).
Ĝenerale, tial la uzata metodaro estas disponebla al ĉiuj kiel eble plej rapide.
Mi provos afiŝi la projekton sur github baldaŭ.
fonto: www.habr.com