Sparql, distance and very long response times

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I am using sparql in a spring boot project.

I created a query that will calculate the distance and then filter if the distance is less than x.

However, I have a very long processing time (around 2 seconds, sometimes +). On my computer I have 32GB of ram, on my production server much less (1GB of ram), but the time is always the same.

    query1
         PREFIX (...)
        PREFIX geof: <http://www.opengis.net/def/function/geosparql/>
        PREFIX geo: <http://www.opengis.net/ont/geosparql#>
        prefix sf: <http://www.opengis.net/ont/sf>
        PREFIX uom: <http://www.opengis.net/def/uom/OGC/1.0/>
                    SELECT
            ?url ?contactUri ?email ?id ?descri_courte ?geo ?lon ?lat ?x ?geom ?lattype ?wkt ?xr ?longitude
            WHERE {
              ?url   :isLocatedAt ?place.
              ?place schema:geo ?geo.## ?place a pour coordonnées géographiques ?geo
            ?geo schema:longitude ?longitude; ## ?geo a pour longitude ?longitude
            schema:latitude ?latitude.
            BIND (STRDT(CONCAT("POINT(",str(?longitude), " ", str(?latitude), ")"),geo:wktLiteral) as ?wkt)
BIND (STRDT(CONCAT("POINT(",str(10.9999), " ", str(52.9999), ")"),geo:wktLiteral) as ?wp2)
              BIND (geof:distance(?wkt, ?wp2,uom:metre) as ?xr)
FILTER(?xr < 2000)

            ?url <https://www.datatourisme.gouv.fr/ontology/core#hasContact> ?contactUri.
              ?contactUri a <https://www.datatourisme.gouv.fr/ontology/core#Agent>.
                      optional {
                        ?contactUri schema:email ?email.
                        }
         ?url dc:identifier ?id.
             Optional { ?url rdfs:label ?descri_courte }
                 Optional { ?place schema:geo ?geo }
              Optional { ?geo schema:longitude ?lon; schema:latitude ?lat. }
              Optional {?geo rdf:type ?lattype}
              Optional {?geo <https://www.datatourisme.gouv.fr/ontology/core#latlon> ?x. }

            }

on the other hand, to make a count, the processing time is clearly faster

  query2:     
    PREFIX (...)
        PREFIX geof: <http://www.opengis.net/def/function/geosparql/>
        PREFIX geo: <http://www.opengis.net/ont/geosparql#>
        prefix sf: <http://www.opengis.net/ont/sf>
        PREFIX uom: <http://www.opengis.net/def/uom/OGC/1.0/>
                    SELECT
                    (count(*) as ?resultat)
                    WHERE {
                      ?url   :isLocatedAt ?place.
                      ?place schema:geo ?geo.## ?place a pour coordonnées géographiques ?geo
                    ?geo schema:longitude ?longitude; ## ?geo a pour longitude ?longitude
                    schema:latitude ?latitude.
                    BIND (STRDT(CONCAT("POINT(",str(?longitude), " ", str(?latitude), ")"),geo:wktLiteral) as ?wkt)
        BIND (STRDT(CONCAT("POINT(",str(10.9999), " ", str(52.9999), ")"),geo:wktLiteral) as ?wp2)
                      BIND (geof:distance(?wkt, ?wp2,uom:metre) as ?xr)
        FILTER(?xr < 2000)
                    }

I use Jena. I have already tried to shorten query 1 but I feel the processing time does not change ... could you please help me improve the performance of my query1?

thanking you

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