Slow query with big tables

From: Tommi Kaksonen <t2nn2t(at)gmail(dot)com>
To: pgsql-performance(at)postgresql(dot)org
Subject: Slow query with big tables
Date: 2016-08-24 11:35:23
Message-ID: CAOLG3nqaw3bymQAAZFLhnZbY8=WMd_Yiy4stZuiMGdHk-3OANg@mail.gmail.com
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Hello,

I have the following tables and query. I would like to get some help to
find out why it is slow and how its performance could be improved.

Thanks,
Tommi K.

*--Table definitions---*
CREATE TABLE "Measurement"
(
id bigserial NOT NULL,
product_id bigserial NOT NULL,
nominal_data_id bigserial NOT NULL,
description text,
serial text,
measurement_time timestamp without time zone,
status smallint,
system_description text,
CONSTRAINT "Measurement_pkey" PRIMARY KEY (id),
CONSTRAINT "Measurement_nominal_data_id_fkey" FOREIGN KEY
(nominal_data_id)
REFERENCES "Nominal_data" (id) MATCH SIMPLE
ON UPDATE NO ACTION ON DELETE NO ACTION,
CONSTRAINT "Measurement_product_id_fkey" FOREIGN KEY (product_id)
REFERENCES "Product" (id) MATCH SIMPLE
ON UPDATE NO ACTION ON DELETE NO ACTION
)
WITH (
OIDS=FALSE
);

CREATE INDEX measurement_time_index
ON "Measurement"
USING btree
(measurement_time);
ALTER TABLE "Measurement" CLUSTER ON measurement_time_index;

CREATE TABLE "Product"
(
id bigserial NOT NULL,
name text,
description text,
info text,
system_name text,
CONSTRAINT "Product_pkey" PRIMARY KEY (id)
)
WITH (
OIDS=FALSE
);

CREATE TABLE "Extra_info"
(
id bigserial NOT NULL,
measurement_id bigserial NOT NULL,
name text,
description text,
info text,
type text,
value_string text,
value_double double precision,
value_integer bigint,
value_bool boolean,
CONSTRAINT "Extra_info_pkey" PRIMARY KEY (id),
CONSTRAINT "Extra_info_measurement_id_fkey" FOREIGN KEY (measurement_id)
REFERENCES "Measurement" (id) MATCH SIMPLE
ON UPDATE NO ACTION ON DELETE NO ACTION
)
WITH (
OIDS=FALSE
);

CREATE INDEX extra_info_measurement_id_index
ON "Extra_info"
USING btree
(measurement_id);

CREATE TABLE "Feature"
(
id bigserial NOT NULL,
measurement_id bigserial NOT NULL,
name text,
description text,
info text,
CONSTRAINT "Feature_pkey" PRIMARY KEY (id),
CONSTRAINT "Feature_measurement_id_fkey" FOREIGN KEY (measurement_id)
REFERENCES "Measurement" (id) MATCH SIMPLE
ON UPDATE NO ACTION ON DELETE NO ACTION
)
WITH (
OIDS=FALSE
);

CREATE INDEX feature_measurement_id_and_name_index
ON "Feature"
USING btree
(measurement_id, name COLLATE pg_catalog."default");

CREATE INDEX feature_measurement_id_index
ON "Feature"
USING hash
(measurement_id);

CREATE TABLE "Point"
(
id bigserial NOT NULL,
feature_id bigserial NOT NULL,
x double precision,
y double precision,
z double precision,
status_x smallint,
status_y smallint,
status_z smallint,
difference_x double precision,
difference_y double precision,
difference_z double precision,
CONSTRAINT "Point_pkey" PRIMARY KEY (id),
CONSTRAINT "Point_feature_id_fkey" FOREIGN KEY (feature_id)
REFERENCES "Feature" (id) MATCH SIMPLE
ON UPDATE NO ACTION ON DELETE NO ACTION
)
WITH (
OIDS=FALSE
);

CREATE INDEX point_feature_id_index
ON "Point"
USING btree
(feature_id);

CREATE TABLE "Warning"
(
id bigserial NOT NULL,
feature_id bigserial NOT NULL,
"number" smallint,
info text,
CONSTRAINT "Warning_pkey" PRIMARY KEY (id),
CONSTRAINT "Warning_feature_id_fkey" FOREIGN KEY (feature_id)
REFERENCES "Feature" (id) MATCH SIMPLE
ON UPDATE NO ACTION ON DELETE NO ACTION
)
WITH (
OIDS=FALSE
);

CREATE INDEX warning_feature_id_index
ON "Warning"
USING btree
(feature_id);

*---Query---*
SELECT
f.name,
f.description,
SUM(CASE WHEN p.status_x = 0 AND p.status_y = 0 AND p.status_z = 0 AND
warning.id IS NULL THEN 1 ELSE 0 END) AS green_count,
SUM(CASE WHEN p.status_x = 0 AND p.status_y = 0 AND p.status_z = 0 AND
warning.id IS NOT NULL THEN 1 ELSE 0 END) AS green_warned_count,
SUM(CASE WHEN NOT (p.status_x = 0 AND p.status_y = 0 AND p.status_z = 0)
AND NOT (p.status_x = 2 OR p.status_y = 2 OR p.status_z = 2) AND warning.id
IS NULL THEN 1 ELSE 0 END) AS yellow_count,
SUM(CASE WHEN NOT (p.status_x = 0 AND p.status_y = 0 AND p.status_z = 0)
AND NOT (p.status_x = 2 OR p.status_y = 2 OR p.status_z = 2) AND warning.id
IS NOT NULL THEN 1 ELSE 0 END) AS yellow_warned_count,
SUM(CASE WHEN (p.status_x = 2 OR p.status_y = 2 OR p.status_z = 2) AND
warning.id IS NULL THEN 1 ELSE 0 END) AS red_count,
SUM(CASE WHEN (p.status_x = 2 OR p.status_y = 2 OR p.status_z = 2) AND
warning.id IS NOT NULL THEN 1 ELSE 0 END) AS red_warned_count,
SUM(CASE WHEN (p.status_x = 1000 OR p.status_y = 1000 OR p.status_z = 1000)
AND warning.id IS NOT NULL THEN 1 ELSE 0 END) AS unable_to_measure_count
FROM "Point" p
JOIN "Feature" f ON f.id = p.feature_id
JOIN "Measurement" measurement ON measurement.id = f.measurement_id
JOIN "Product" product ON product.id = measurement.product_id
LEFT JOIN "Warning" warning ON f.id = warning.feature_id
WHERE (product.name ILIKE 'Part 1') AND
measurement.measurement_start_time >= '2015-06-18 17:00:00' AND
measurement.measurement_start_time <= '2015-06-18 18:00:00' AND
measurement.id NOT IN(SELECT measurement_id FROM "Extra_info" e
WHERE e.measurement_id = measurement.id AND e.description = 'Clamp' AND
e.value_string ILIKE 'Clamped%')
GROUP BY f.name, f.description;

*---Explain Analyze---*
GroupAggregate (cost=1336999.08..1337569.18 rows=5562 width=33) (actual
time=6223.622..6272.321 rows=255 loops=1)
Buffers: shared hit=263552 read=996, temp read=119 written=119
-> Sort (cost=1336999.08..1337012.98 rows=5562 width=33) (actual
time=6223.262..6231.106 rows=26265 loops=1)
Sort Key: f.name, f.description
Sort Method: external merge Disk: 936kB
Buffers: shared hit=263552 read=996, temp read=119 written=119
-> Nested Loop Left Join (cost=0.00..1336653.08 rows=5562
width=33) (actual time=55.792..6128.875 rows=26265 loops=1)
Buffers: shared hit=263552 read=996
-> Nested Loop (cost=0.00..1220487.17 rows=5562 width=33)
(actual time=55.773..5910.852 rows=26265 loops=1)
Buffers: shared hit=182401 read=954
-> Nested Loop (cost=0.00..22593.53 rows=8272
width=27) (actual time=30.980..3252.869 rows=38831 loops=1)
Buffers: shared hit=972 read=528
-> Nested Loop (cost=0.00..657.24 rows=22
width=8) (actual time=0.102..109.577 rows=103 loops=1)
Join Filter: (measurement.product_id =
product.id)
Rows Removed by Join Filter: 18
Buffers: shared hit=484 read=9
-> Seq Scan on "Product" product
(cost=0.00..1.04 rows=1 width=8) (actual time=0.010..0.019 rows=1 loops=1)
Filter: (name ~~* 'Part 1'::text)
Rows Removed by Filter: 2
Buffers: shared hit=1
-> Index Scan using
measurement_start_time_index on "Measurement" measurement
(cost=0.00..655.37 rows=67 width=16) (actual time=0.042..109.416 rows=121
loops=1)
Index Cond: ((measurement_start_time
>= '2015-06-18 17:00:00'::timestamp without time zone) AND
(measurement_start_time <= '2015-06-18 18:00:00'::timestamp without time
zone))
Filter: (NOT (SubPlan 1))
Buffers: shared hit=483 read=9
SubPlan 1
-> Index Scan using
extra_info_measurement_id_index on "Extra_info" e (cost=0.00..9.66 rows=1
width=8) (actual time=0.900..0.900 rows=0 loops=121)
Index Cond: (measurement_id =
measurement.id)
Filter: ((value_string ~~*
'Clamped%'::text) AND (description = 'Clamp'::text))
Rows Removed by Filter: 2
Buffers: shared hit=479 read=7
-> Index Scan using
feature_measurement_id_and_name_index on "Feature" rf (cost=0.00..993.40
rows=370 width=35) (actual time=28.152..30.407 rows=377 loops=103)
Index Cond: (measurement_id = measurement.id
)
Buffers: shared hit=488 read=519
-> Index Scan using point_feature_id_index on "Point"
p (cost=0.00..144.80 rows=1 width=14) (actual time=0.067..0.067 rows=1
loops=38831)
Index Cond: (feature_id = f.id)
Buffers: shared hit=181429 read=426
-> Index Scan using warning_feature_id_index on "Warning"
warning (cost=0.00..20.88 rows=1 width=16) (actual time=0.007..0.007
rows=0 loops=26265)
Index Cond: (f.id = feature_id)
Buffers: shared hit=81151 read=42
Total runtime: 6273.312 ms

*---Version---*
PostgreSQL 9.2.1, compiled by Visual C++ build 1600, 64-bit

*---Table sizes---*
Extra_info 1223400 rows
Feature 185436000 rows
Measurement 500000 rows
Point 124681000 rows
Warning 11766800 rows

*---Hardware---*
Intel Core i5-2320 CPU 3.00GHz (4 CPUs)
6GB Memory
64-bit Operating System (Windows 7 Professional)
WD Blue 500GB HDD - 7200 RPM SATA 6 Gb/s 16MB Cache

*---History---*
Query gets slower as more data is added to the database

*---Maintenance---*
Autovacuum is used with default settings

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