Re: Memory leak (possibly connected to postgis) leading to server crash

On Tue, Dec 17, 2019 at 12:51:27PM +0100, Roman Cervenak wrote:
>Hey guys,
>I have reproducer for you.
>
>Luckily, the issue is not specific for our data, and can be demonstrated
>also on OpenStreepMap data. I have imported OSM planet with Imposm, which
>creates tables with PostGIS geometry columns.
>I have used roads for linestring testing and landuse for polygon testing,
>with queries combining several geometric operations (similar to my
>production workload).
>
>The linesting test with 7 concurrent workers increases memory consumption
>by about 6 GB per hour on my environment.
>
>If you don't have OSM database with geometries, I have dumped the roads
>table (about 25GB download):
>https://sygicpublic.blob.core.windows.net/postgres-bug-data/osm_road.sql.gzip
>Here is the tool running queries in parallel workers, written in .NET Core
>(just fill in database connection info in Program.cs, build and run):
>https://github.com/rouen-sk/PostgisMemoryLeakDemoCore
>
>Let me know if I can help further.
>

I'll try reproducing it, but I don't have any environment to run c#
stuff. Is it possible to reproduce a single query reproducing the issue,
with fixed parameters? Or is the randomization necessary?

regards

--
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services