How to use warmup?

[Kevin-Darty]

I could not find any information about warmup or WARMUP_CMD on documentation, nor code, nor the doc repo https://github.com/qlever-dev/qlever-docs.

See https://docs.qlever.dev/

Related to #177 ?

What is the benefit for Qlever to execute this warmup query?

[Kevin-Darty]

There is a single example without explanation:

qlever-control/src/qlever/Qleverfiles/Qleverfile.ohm-planet

Line 34 in 0364626

WARMUP_CMD = curl -s https://qlever.cs.uni-freiburg.de/petrimaps/query --data-urlencode "query=PREFIX geo: <http://www.opengis.net/ont/geosparql#> PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX osm: <https://www.openstreetmap.org/> SELECT ?osm_id ?geometry WHERE { ?osm_id geo:hasGeometry/geo:asWKT ?geometry . ?osm_id rdf:type osm:node } LIMIT 1" --data-urlencode "backend=https://qlever.cs.uni-freiburg.de/api/${data:NAME}" > /dev/null

[Qup42]

qlever start --help gives a little info: Command executed after the server has started (executed as part of ´qlever start´ unless ´--no-warmup´ is specified, or with ´qlever warmup´). In general the warmup command can be used to fill caches for faster execution later on. In the case you found it loads all the geo geometries into petrimaps which takes some time and would happen happen with the first actual request otherwise. It can also be used to run some queries which will then already be cached when users execute them. But this is not required it is just to make things faster.