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PostgreSQL-da blokirovkalar tarixini olish usullaridan biri

Maqolaning davomi "PostgreSQL uchun ASH analogini yaratishga urinish ".

Maqolada pg_locks ko'rinishi tarixidan qanday foydali ma'lumotlarni olish mumkinligi aniq so'rovlar va misollar yordamida ko'rib chiqiladi va ko'rsatiladi.

Ogohlantirish.
Mavzuning yangiligi va test davrining to'liq bo'lmaganligi sababli maqolada xatolar bo'lishi mumkin. Tanqid va sharhlar qabul qilinadi va kutiladi.

Ma'lumotlarni kiritish

pg_locks taqdimoti tarixi

arxiv_qulflash

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 
);

Umuman olganda, jadval jadvalga o'xshaydi archive_pg_stat_activity, bu erda batafsil tavsiflangan - pg_stat_statements + pg_stat_activity + loq_query = pg_ash? va bu erda - PostgreSQL uchun ASH analogini yaratishga urinish.

Ustunni to'ldirish uchun so'rov id funksiyasidan foydalaniladi

yangilash_history_locking_by_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;

Izoh: so'rov ustunining qiymati history_locking jadvalida yangilanadi va keyin archive_locking jadvali uchun yangi bo'lim yaratilganda, qiymat tarixiy qiymatlarda saqlanadi.

Chiqish

Umumiy jarayonlar haqida umumiy ma'lumot.

LOCKTYPLAR BO'YICHA QULFLARNI KUTISH

So'rov

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

misol

| LOCKTYPLAR BO'YICHA QULFLARNI KUTISH
+---------------------------------+----------------------- --+-------------------
| locktype| rejimi| davomiyligi
+---------------------------------+----------------------- --+-------------------
| tranzaksiyaid| ShareLock| 19:39:26
| tuple| AccessExclusiveLock| 00:03:35
+---------------------------------+----------------------- --+-------------------

QULFLARNI QULF TYPLARI BILAN OLISH

So'rov

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

misol

| QULFLARNI QULF TYPLARI BILAN OLISH
+---------------------------------+----------------------- --+-------------------
| locktype| rejimi| davomiyligi
+---------------------------------+----------------------- --+-------------------
| munosabat| RowExclusiveLock| 51:11:10
| virtualxid| ExclusiveLock| 48:10:43
| tranzaksiyaid| ExclusiveLock| 44:24:53
| munosabat| AccessShareLock| 20:06:13
| tuple| AccessExclusiveLock| 17:58:47
| tuple| ExclusiveLock| 01:40:41
| munosabat| ShareUpdateExclusiveLock| 00:26:41
| ob'ekt| RowExclusiveLock| 00:00:01
| tranzaksiyaid| ShareLock| 00:00:01
| uzaytirish| ExclusiveLock| 00:00:01
+---------------------------------+----------------------- --+-------------------

Muayyan so'rovlar bo'yicha batafsil ma'lumot

QUERYID BO'YICHA LOCKTYPLAR BO'YICHA QULFLARNI KUTISH

So'rov

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

misol

| QUERYID BO'YICHA LOCKTYPLAR BO'YICHA QULFLARNI KUTISH
+----------+----------+------------ --------+------ -----------------+--------- ----------+------- -------------+------------------- --
| pid| locktype| rejimi| boshlandi| queryid| blocking_pids| davomiyligi
+----------+----------+------------ --------+------ -----------------+--------- ----------+------- -------------+------------------- --
| 11288| tranzaksiyaid| ShareLock| 2019-09-17 10:00:00.302936| 389015618226997618| {11092}| 00:03:34
| 11626| tranzaksiyaid| ShareLock| 2019-09-17 10:00:21.380921| 389015618226997618| {12380}| 00:00:29
| 11626| tranzaksiyaid| ShareLock| 2019-09-17 10:00:21.380921| 389015618226997618| {11092}| 00:03:25
| 11626| tranzaksiyaid| ShareLock| 2019-09-17 10:00:21.380921| 389015618226997618| {12213}| 00:01:55
| 11626| tranzaksiyaid| ShareLock| 2019-09-17 10:00:21.380921| 389015618226997618| {12751}| 00:00:01
| 11629| tranzaksiyaid| ShareLock| 2019-09-17 10:00:24.331935| 389015618226997618| {11092}| 00:03:22
| 11629| tranzaksiyaid| ShareLock| 2019-09-17 10:00:24.331935| 389015618226997618| {12007}| 00:00:01
| 12007| tranzaksiyaid| ShareLock| 2019-09-17 10:05:03.327933| 389015618226997618| {11629}| 00:00:13
| 12007| tranzaksiyaid| ShareLock| 2019-09-17 10:05:03.327933| 389015618226997618| {11092}| 00:01:10
| 12007| tranzaksiyaid| ShareLock| 2019-09-17 10:05:03.327933| 389015618226997618| {11288}| 00:00:05
| 12213| tranzaksiyaid| ShareLock| 2019-09-17 10:06:07.328019| 389015618226997618| {12007}| 00:00:10

QUERYID BO'YICHA LOCKTYPLAR BO'YICHA QULFLAR OLISH

So'rov

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

misol

| QUERYID BO'YICHA LOCKTYPLAR BO'YICHA QULFLAR OLISH
+----------+----------+------------ --------+------ -----------------+--------- ----------+------- -----------------------+------------------ --
| pid| locktype| rejimi| boshlandi| queryid| blocking_pids| davomiyligi
+----------+----------+------------ --------+------ -----------------+--------- ----------+------- -----------------------+------------------ --
| 11288| munosabat| RowExclusiveLock| 2019-09-17 10:00:00.302936| 389015618226997618| {11092}| 00:03:34
| 11092| tranzaksiyaid| ExclusiveLock| 2019-09-17 10:00:00.302936| 389015618226997618| {}| 00:03:34
| 11288| munosabat| RowExclusiveLock| 2019-09-17 10:00:00.302936| 389015618226997618| {}| 00:00:10
| 11092| munosabat| RowExclusiveLock| 2019-09-17 10:00:00.302936| 389015618226997618| {}| 00:03:34
| 11092| virtualxid| ExclusiveLock| 2019-09-17 10:00:00.302936| 389015618226997618| {}| 00:03:34
| 11288| virtualxid| ExclusiveLock| 2019-09-17 10:00:00.302936| 389015618226997618| {11092}| 00:03:34
| 11288| tranzaksiyaid| ExclusiveLock| 2019-09-17 10:00:00.302936| 389015618226997618| {11092}| 00:03:34
| 11288| tuple| AccessExclusiveLock| 2019-09-17 10:00:00.302936| 389015618226997618| {11092}| 00:03:34

Ishlash hodisalarini tahlil qilish uchun qulflash tarixidan foydalanish.

  1. Queryid=389015618226997618 soΚ»rovi pid=11288 boΚ»lgan jarayon tomonidan bajarilgan, 2019-09-17 soat 10:00:00 dan boshlab 3 daqiqa davomida bloklanishni kutayotgan edi.
  2. Qulflash pid=11092 bo'lgan jarayon tomonidan ushlab turilgan
  3. 11092-389015618226997618-2019 dan 09:17:10 dan boshlab queryid=00 soβ€˜rovni bajaruvchi pid=00 boβ€˜lgan jarayon 3 daqiqa davomida qulfni ushlab turdi.

Xulosa

Endi umid qilamanki, eng qiziqarli va foydali qism boshlanadi - statistik ma'lumotlarni yig'ish va kutish va blokirovkalar tarixi bo'yicha ishlarni tahlil qilish.

Kelajakda biz bir nechta eslatmalar to'plamini olamiz (Oracle metalinkiga o'xshash) ishonmoqchiman.

Umuman olganda, aynan shuning uchun foydalanilgan metodologiya hamma uchun imkon qadar tezroq taqdim etiladi.

Yaqin kelajakda loyihani github-ga joylashtirishga harakat qilaman.

Manba: www.habr.com

a Izoh qo'shish