In order to evaluate the performance of Sparkwave, we defined some tests reusing part of the dataset from the Berlin SPARQL Benchmark (BSBM). The BSBM defines a suite of benchmarks to compare the performance of RDF stores and, in general, of storage systems that expose SPARQL endpoints. The benchmark is built around an e-commerce use case in which a set of products is offered by different vendors, and consumers have posted reviews about the products.

The BSBM is not intended for measuring stream processing systems and by itself does not provide data streams, so we had to adapt it to our needs. In particular, we reused the data describing product types and offers. The BSBM generates a single-rooted hierarchy of product types, whose depth and number of classes are determined by a scaling factor; each product is then assigned to a product type at the leaf level of the hierarchy. The hierarchy of product types constitutes for us the schema. The BSBM also generates a number of offers related to products, which for us constitute the data stream.

Given these schema and stream from the BSBM, we defined three graph patterns:

• In pattern 1 we look for offers for products of a given type; for non-leaf types, inference needs to take place on the hierarchy of product types. There are no static instances.
• Additionally to the conditions set in pattern 1, in pattern 2 we only want offers for which the vendor is from a given country. The binding between vendors and countries is given through static instances.
• Additionally to the conditions set in pattern 2, in pattern 3 we only want offers for products for which the producer is from a given country. The binding between producers and countries is given through static instances.

	-- Pattern 1: ------------------------------------------------------------------------
	
	REGISTER QUERY BSBSOfferDetection AS
	PREFIX bsbm-voc:<http://www4.wiwiss.fu-berlin.de/bizer/bsbm/v01/vocabulary/>
	PREFIX bsbm-inst:<http://www4.wiwiss.fu-berlin.de/bizer/bsbm/v01/instances/>
	PREFIX rdf:<http://www.w3.org/1999/02/22-rdf-syntax-ns#>
	PREFIX dc:<http://purl.org/dc/elements/1.1/>
	SELECT ?offer ?product ?vendor ?price ?from ?to ?delivery ?webpage
		   ?publisher ?date
	FROM STREAM <http://bsbm.org/stream>
	FROM <http://members.sti2.at/~srdjank/ProductTypeHierarchy.rdf>
	WHERE {
		?offer rdf:type bsbm-voc:Offer.
		?offer bsbm-voc:product ?product.
		?offer bsbm-voc:vendor ?vendor.
		?offer bsbm-voc:price ?price.
		?offer bsbm-voc:validFrom ?from.
		?offer bsbm-voc:validTo ?to.
		?offer bsbm-voc:deliveryDays ?delivery.
		?offer bsbm-voc:offerWebpage ?webpage.
		?offer dc:publisher ?publisher.
		?offer dc:date ?date.
		?product rdf:type bsbm-inst:TargetProductType
	}
	
	-- Pattern 2: additionally to pattern 1, in WHERE clause: ------------------------------
		?vendor bsbm-voc:country http://downlode.org/rdf/iso-3166/countries#GB
	
	-- Pattern 3: additionally to pattern 1, in WHERE clause: ------------------------------
		?vendor bsbm-voc:country http://downlode.org/rdf/iso-3166/countries#GB
		?product bsbm-voc:producer ?producer
		?producer bsbm-voc:country http://downlode.org/rdf/iso-3166/countries#DE
			  

Memory consumption over time window size

Throughput over time window size

Throughput over background knowledge size