[postgis-users] Performance problems with ST_Union on postgres 9.6, postgis 2.4.3 running on top of Red Hat 7.4
Jonas Nygaard Pedersen
jonyp at sdfe.dk
Tue Apr 24 04:57:48 PDT 2018
Hi Regina
I’ve enclosed a sample dataset of 31489 rows (enclosed in separate email to Regina) that I hope can serve as a basis for more tests. It’s definitely not top secret, just building polygons for an area in Western Jutland, Denmark (the total dataset would be for all of Denmark).
It should be noted that both the windows and redhat machine are specked with NVMe ssd disks that holds the postgres instance and data.
The windows machine has 64 and the redhat has 128 GB of ram. Both have fairly recent workstation/server-grade cpus.
Windows:
'POSTGIS="2.3.2 r15302" GEOS="3.5.0-CAPI-1.9.0 r4084" PROJ="Rel. 4.9.2, 08 September 2015" GDAL="GDAL 1.11.5, released 2016/07/01" LIBXML="2.9.4" TOPOLOGY RASTER'
‘PostgreSQL 9.6.3 on x86_64-pc-mingw64, compiled by gcc.exe (Rev5, Built by MSYS2 project) 4.9.2, 64-bit’
Red Hat 7.4:
'POSTGIS="2.4.3 r16312" PGSQL="96" GEOS="3.6.2-CAPI-1.10.2 4d2925d6" SFCGAL="1.2.2" PROJ="Rel. 4.9.3, 15 August 2016" GDAL="GDAL 1.11.4, released 2016/01/25" LIBXML="2.9.1" LIBJSON="0.11" RASTER'
‘PostgreSQL 9.6.8 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-16), 64-bit’
On the windows version the statement:
select
st_multi((st_dump(geom)).geom)::geometry(multipolygon,25832) as geom
from (
select st_union(b.geom) as geom
from temp_jonyp.st_union_test b
) foo
;
Runs with a ‘Total query runtime: 19.5 secs 18423 rows retrieved.’
The same statement and data on the redhat machine runs with a ‘Total query runtime: 01:17 minutes 18423 rows retrieved.’
Both have almost identical execution plans:
Subquery Scan on foo (cost=1428.62..1433.88 rows=1000 width=32)
-> Aggregate (cost=1428.62..1428.62 rows=1 width=32)
-> Seq Scan on st_union_test b (cost=0.00..1349.89 rows=31489 width=170)
Both have been vacuumed and analyzed beforehand. And max_parallel_workers have been set to 0 on the redhat machine.
I haven’t tried to do a postgis ticket, but let me know if you need that instead.
Kind regards Jonas
Fra: postgis-users [mailto:postgis-users-bounces at lists.osgeo.org] På vegne af Regina Obe
Sendt: 24. april 2018 09:07
Til: 'PostGIS Users Discussion' <postgis-users at lists.osgeo.org>
Emne: Re: [postgis-users] Performance problems with ST_Union on postgres 9.6, postgis 2.4.3 running on top of Red Hat 7.4
Couple of things to try
1) Can you reduce the dataset down a bit to the point you can run it in a reasonable amount of time and see differences?
2) On the 2.4.3 plan I see it is running using parallel mode, can you turn off the parallel to rule that out as an issue.
Set max_parallel_workers_per_gather = 0;
I don't know what your 2.4.2 was running, but for 2.3, it probably wouldn't run in parallel just because fewer functions were flagged as parallel safe
If you can reduce the set some something reasonable where we can test, I'd be happy to test on various OS/ PostGIS config.
I wouldn't rule out a regression issue on our end.
You can provide a sample on a postgis ticket, if it's not too top secret or just send directly to me.
http://postgis.net/support/
Thanks,
Regina
From: postgis-users [mailto:postgis-users-bounces at lists.osgeo.org] On Behalf Of Jonas Nygaard Pedersen
Sent: Monday, April 23, 2018 11:15 AM
To: 'postgis-users at lists.osgeo.org' <postgis-users at lists.osgeo.org<mailto:postgis-users at lists.osgeo.org>>
Subject: [postgis-users] Performance problems with ST_Union on postgres 9.6, postgis 2.4.3 running on top of Red Hat 7.4
Hi list
I'm facing some performance issues when trying to execute the following query on a Red Hat 7.4 machine with Postgres 9.6 (PostgreSQL 9.6.8 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-16), 64-bit) and postgis 2.4.3:
select st_multi((st_dump(geom)).geom)::geometry(multipolygon,25832) as geom
from (
select st_union(b.geom) as geom
from b.gdk_bygning b
) foo;
Previously the statement above finished in about 3.5 hours but now it seems to go on forever, and I'll cancel it after 3 days.
The table contains 5310482 rows and the CREATE TABLE statement looks like this:
CREATE TABLE b.gdk_bygning
(
id_lokalid bigint,
objektstatus character varying(4000),
registreringfra timestamp(6) without time zone,
virkningfra timestamp(6) without time zone,
plannoejagtighed double precision,
vertikalnoejagtighed double precision,
bygninguuid character varying(4000),
bygningstype character varying(4000),
underminimumbygning character varying(5),
status character varying(4000),
geom geometry(Polygon,25832)
)
Indexes:
CREATE INDEX gdk_bygning_id_lokalid_idx
ON b.gdk_bygning
USING btree
(id_lokalid);
CREATE INDEX sidx_gdk_bygning_geom
ON b.gdk_bygning
USING gist
(geom);
I'm not sure where the issue stems from, but from an approximation of when the issue started and near coincidental update from postgis 2.4.1 to 2.4.3, I suspect that the issue is rooted here, and probably combined with some clumsy settings in my postgresql.conf file.
Below I have compiled some documentation that I think will be relevant:
* the original Postgis install with 'yum',
* the update with 'yum',
* what I think are the relevant settings from my postgresql.conf,
* the query plan for the statement on the current 2.4.3 postgis version,
* and lastly the query plan on a windows machine running postgis 2.3.2 (I'm not able to roll back to 2.4.1 with GEOS 3.5).
The only thing that stands out to me is that the GEOS version is upgraded from 3.5.0 to 3.6.2 but I'm definitely unsure about what's going on and I hope that someone on the list can give me some advice.
Regards Jonas
OUTPUT OF 'yum history info' FOR ORIGINAL INSTALL OF POSTGIS:
Loaded plugins: langpacks, product-id, rhnplugin, search-disabled-repos, subscription-manager
This system is receiving updates from RHN Classic or Red Hat Satellite.
Transaction ID : 7
Begin time : Mon Oct 9 17:56:25 2017
Begin rpmdb : 1379:99b8afbfabf2cf72ff17087d17a2a1607e29a909
End time : 17:56:35 2017 (10 seconds)
End rpmdb : 1421:bd1fa883ae52216121f1a7c6a2eb06d2d6e36075
User : <b031513>
Return-Code : Success
Command Line : install postgis24_96.x86_64 postgis24_96-client.x86_64 postgis24_96-devel.x86_64 postgis24_96-utils.x86_64 SFCGAL.x86_64 pgrouting_96.x86_64
Transaction performed with:
Installed rpm-4.11.3-25.el7.x86_64 @rhel-x86_64-server-7
Updated subscription-manager-1.19.21-1.el7.x86_64 @rhel-x86_64-server-7
Installed yum-3.4.3-154.el7.noarch @rhel-x86_64-server-7
Installed yum-metadata-parser-1.1.4-10.el7.x86_64 @anaconda/7.2
Installed yum-rhn-plugin-2.0.1-9.el7.noarch @rhel-x86_64-server-7
Packages Altered:
Dep-Install CGAL-4.7-1.rhel7.x86_64 @pgdg96
Dep-Install CharLS-1.0-5.el7.x86_64 @rhel-x86_64-server-7-epel
Install SFCGAL-1.2.2-1.rhel7.x86_64 @pgdg96
Dep-Install SFCGAL-libs-1.2.2-1.rhel7.x86_64 @pgdg96
Dep-Install armadillo-4.320.0-1.el7.x86_64 @rhel-x86_64-server-7-epel
Dep-Install arpack-3.1.3-2.el7.x86_64 @rhel-x86_64-server-7-epel
Dep-Install atlas-3.10.1-12.el7.x86_64 @rhel-x86_64-server-7
Dep-Install blas-3.4.2-8.el7.x86_64 @rhel-x86_64-server-7
Dep-Install boost-atomic-1.53.0-27.el7.x86_64 @rhel-x86_64-server-7
Dep-Install boost-chrono-1.53.0-27.el7.x86_64 @rhel-x86_64-server-7
Dep-Install boost-serialization-1.53.0-27.el7.x86_64 @rhel-x86_64-server-7
Dep-Install cfitsio-3.370-1.el7.x86_64 @rhel-x86_64-server-7-epel
Dep-Install freexl-1.0.0i-1.el7.x86_64 @rhel-x86_64-server-7-epel
Dep-Install gdal-libs-1.11.4-10.rhel7.x86_64 @pgdg96
Dep-Install geos-3.5.0-1.rhel7.x86_64 @pgdg96
Dep-Install hdf5-1.8.12-8.el7.x86_64 @rhel-x86_64-server-7-epel
Dep-Install lapack-3.4.2-8.el7.x86_64 @rhel-x86_64-server-7
Dep-Install libdap-3.13.1-2.el7.x86_64 @rhel-x86_64-server-7-epel
Dep-Install libgeotiff-1.4.0-1.rhel7.x86_64 @pgdg96
Dep-Install libgfortran-4.8.5-16.el7.x86_64 @rhel-x86_64-server-7
Dep-Install libgta-1.0.4-1.el7.x86_64 @rhel-x86_64-server-7-epel
Dep-Install libquadmath-4.8.5-16.el7.x86_64 @rhel-x86_64-server-7
Dep-Install netcdf-4.3.3.1-5.el7.x86_64 @rhel-x86_64-server-7-epel
Dep-Install ogdi-3.2.0-0.19.beta2.el7.x86_64 @rhel-x86_64-server-7-epel
Dep-Install openjpeg2-2.1.0-7.el7.x86_64 @rhel-x86_64-server-7-epel
Dep-Install perl-Compress-Raw-Bzip2-2.061-3.el7.x86_64 @rhel-x86_64-server-7
Dep-Install perl-Compress-Raw-Zlib-1:2.061-4.el7.x86_64 @rhel-x86_64-server-7
Dep-Install perl-DBD-Pg-2.19.3-4.el7.x86_64 @rhel-x86_64-server-7
Dep-Install perl-DBI-1.627-4.el7.x86_64 @rhel-x86_64-server-7
Dep-Install perl-Data-Dumper-2.145-3.el7.x86_64 @rhel-x86_64-server-7
Dep-Install perl-IO-Compress-2.061-2.el7.noarch @rhel-x86_64-server-7
Dep-Install perl-Net-Daemon-0.48-5.el7.noarch @rhel-x86_64-server-7
Dep-Install perl-PlRPC-0.2020-14.el7.noarch @rhel-x86_64-server-7
Dep-Install perl-version-3:0.99.07-2.el7.x86_64 @rhel-x86_64-server-7
Install pgrouting_96-2.5.0-1.rhel7.x86_64 @pgdg96
Install postgis24_96-2.4.0-1.rhel7.x86_64 @pgdg96
Install postgis24_96-client-2.4.0-1.rhel7.x86_64 @pgdg96
Install postgis24_96-devel-2.4.0-1.rhel7.x86_64 @pgdg96
Install postgis24_96-utils-2.4.0-1.rhel7.x86_64 @pgdg96
Dep-Install proj-4.8.0-4.el7.x86_64 @rhel-x86_64-server-7-epel
Dep-Install unixODBC-2.3.1-11.el7.x86_64 @rhel-x86_64-server-7
Dep-Install xerces-c-3.1.1-8.el7_2.x86_64 @rhel-x86_64-server-7
history info
OUTPUT OF 'yum history info' FOR THE UPDATE:
Loaded plugins: langpacks, product-id, rhnplugin, search-disabled-repos, subscription-manager
This system is receiving updates from RHN Classic or Red Hat Satellite.
Transaction ID : 35
Begin time : Tue Apr 3 11:30:58 2018
Begin rpmdb : 1748:db6ede4f0b0b9815a1f8704452181b47f0a32796
End time : 11:31:04 2018 (6 seconds)
End rpmdb : 1749:83a1f934015ebd6db6adc07214b1937477780af4
User : <b031513>
Return-Code : Success
Command Line : update postgis
Transaction performed with:
Installed rpm-4.11.3-25.el7.x86_64 @rhel-x86_64-server-7
Installed subscription-manager-1.19.23-1.el7_4.x86_64 @rhel-x86_64-server-7
Installed yum-3.4.3-154.el7.noarch @rhel-x86_64-server-7
Installed yum-metadata-parser-1.1.4-10.el7.x86_64 @anaconda/7.2
Installed yum-rhn-plugin-2.0.1-9.el7.noarch @rhel-x86_64-server-7
Packages Altered:
Dep-Install geos36-3.6.2-3.1.rhel7.x86_64 @pgdg96
Updated postgis24_96-2.4.1-1.rhel7.x86_64 @pgdg96
Update 2.4.3-1.rhel7.x86_64 @pgdg96
Updated postgis24_96-client-2.4.1-1.rhel7.x86_64 @pgdg96
Update 2.4.3-1.rhel7.x86_64 @pgdg96
Updated postgis24_96-devel-2.4.1-1.rhel7.x86_64 @pgdg96
Update 2.4.3-1.rhel7.x86_64 @pgdg96
Updated postgis24_96-utils-2.4.1-1.rhel7.x86_64 @pgdg96
Update 2.4.3-1.rhel7.x86_64 @pgdg96
history info
WHAT I THINK ARE THE RELEVANT OPTIONS IN MY 'postgresql.conf' THAT ARE DIFFERENT FROM THE ONE THAT CAME WITH 9.6 FROM 'pgdg96' REPOSITORY:
shared_buffers = 50GB # min 128kB
# (change requires restart)
#huge_pages = try # on, off, or try
# (change requires restart)
#temp_buffers = 8MB # min 800kB
#max_prepared_transactions = 0 # zero disables the feature
# (change requires restart)
work_mem = 5GB # min 64kB
maintenance_work_mem = 5GB
#replacement_sort_tuples = 150000 # limits use of replacement selection sort
#autovacuum_work_mem = -1 # min 1MB, or -1 to use maintenance_work_mem
#max_stack_depth = 2MB # min 100kB
dynamic_shared_memory_type = posix # the default is the first option
effective_io_concurrency = 200 # 1-1000; 0 disables prefetching
max_worker_processes = 64 # (change requires restart)
max_parallel_workers_per_gather = 12 # taken from max_worker_processes
seq_page_cost = 1.0 # measured on an arbitrary scale
random_page_cost = 2.0 # same scale as above
#cpu_tuple_cost = 0.01 # same scale as above
#cpu_index_tuple_cost = 0.005 # same scale as above
#cpu_operator_cost = 0.0025 # same scale as above
parallel_tuple_cost = 0.001 # same scale as above
parallel_setup_cost = 100.0 # same scale as above
#min_parallel_relation_size = 8MB
effective_cache_size = 90GB
QUERY PLAN AFTER UPDATE TO POSTGIS 2.4.3 ('POSTGIS="2.4.3 r16312" PGSQL="96" GEOS="3.6.2-CAPI-1.10.2 4d2925d6" SFCGAL="1.2.2" PROJ="Rel. 4.9.3, 15 August 2016" GDAL="GDAL 1.11.4, released 2016/01/25" LIBXML="2.9.1" LIBJSON="0.11" RASTER')
QUERY PLAN
-----------------------------------------------------------------------------------------------------
Subquery Scan on foo (cost=231732.65..231737.92 rows=1000 width=32)
-> Aggregate (cost=231732.65..231732.66 rows=1 width=32)
-> Gather (cost=100.00..218456.45 rows=5310482 width=169)
Workers Planned: 5
-> Parallel Seq Scan on gdk_bygning b (cost=0.00..213045.96 rows=1062096 width=169)
(5 rows)
QUERY PLAN ON WINDOWS MACHINE ('POSTGIS="2.3.2 r15302" GEOS="3.5.0-CAPI-1.9.0 r4084" PROJ="Rel. 4.9.2, 08 September 2015" GDAL="GDAL 1.11.5, released 2016/07/01" LIBXML="2.9.4" TOPOLOGY RASTER'):
QUERY PLAN
-------------------------------------------------------------------------------------
Subquery Scan on foo (cost=216558.28..216563.55 rows=1000 width=32)
-> Aggregate (cost=216558.28..216558.29 rows=1 width=32)
-> Seq Scan on gdk_bygning b (cost=0.00..204498.02 rows=4824102 width=175)
Jonas Nygaard Pedersen │Geodataanalytiker │Eff – Effektivisering│Tel. 7254 5510│jonyp at sdfe.dk
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/postgis-users/attachments/20180424/2153d437/attachment.html>
More information about the postgis-users
mailing list