Hello all ;-)
I ported the code to Chez Scheme to do an apple-to-apple comparison between GNU Guile and Chez and took the time to launch a few queries against Virtuoso available in Ubuntu 18.04 (LTS). Spoiler: the new code is always faster. The hard disk is SATA, and the CPU is dubbed: Intel(R) Xeon(R) CPU E3-1220 V2 @ 3.10GHz I imported latest-lexeme.nt (6GB) using guile-nomunofu, chez-nomunofu and Virtuoso: - Chez takes 40 minutes to import 6GB - Chez is 3 to 5 times faster than Guile - Chez is 11% faster than Virtuoso Regarding query time, Chez is still faster than Virtuoso with or without cache. The query I am testing is the following: SELECT ?s ?p ?o FROM <http://fu> WHERE { ?s <http://purl.org/dc/terms/language> <http://www.wikidata.org/entity/Q150> . ?s <http://wikiba.se/ontology#lexicalCategory> <http://www.wikidata.org/entity/Q1084> . ?s <http://www.w3.org/2000/01/rdf-schema#label> ?o }; Virtuoso first query takes: 1295 msec. The second query takes: 331 msec. Then it stabilize around: 200 msec. chez nomunofu takes around 200ms without cache. There is still an optimization I can do to speed up nomunofu a little. Happy hacking!