serqlperftest.java

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package org.openrdf.sesame.query.serql;

import java.net.URL;

import org.openrdf.sesame.constants.QueryLanguage;
import org.openrdf.sesame.query.QueryResultsTable;
import org.openrdf.sesame.repository.remote.HTTPRepository;
import org.openrdf.sesame.repository.remote.HTTPService;

/**
 * Performance test that sends SeRQL queries to a Sesame server and
 * measures the average time it takes to send a query and parse the
 * query results.
 */
public class SeRQLPerfTest {

/*--------------------+
| Constants           |
+--------------------*/

	public static final String SERVER_URL = "http://localhost/sesame/";

	//public static final String REPOSITORY = "mem-rdf-db";
	//public static final String REPOSITORY = "mem-rdfs-db";
	public static final String REPOSITORY = "rdf-mysql-db";
	//public static final String REPOSITORY = "rdfs-mysql-db";

	// test query 1 (1 result)
	public static final String QUERY1 =
			"select Country, Name " +
			"from {Country} <ciafb:Name> {Name}; " +
			               "<ciafb:Map_references> {\"Africa\"}; " +
			               "<ciafb:Natural_resources> {\"oil\"} " +
			"using namespace " +
			"ciafb = <!http://www.cia.gov/cia/publications/factbook#>";

	// test query 2 (12 results)
	public static final String QUERY2 =
			"select Country, Name " +
			"from {Country} <ciafb:Name> {Name}; " +
			               "<ciafb:Map_references> {\"Africa\"}; " +
			               "<ciafb:Natural_resources> {\"petroleum\"} " +
			"using namespace " +
			"ciafb = <!http://www.cia.gov/cia/publications/factbook#>";

	// test query 3 (247 results)
	public static final String QUERY3 =
			"select Country, Name, NatRes " +
			"from {Country} <ciafb:Name> {Name}; " +
			               "<ciafb:Map_references> {\"Africa\"}; " +
			               "<ciafb:Natural_resources> {NatRes} " +
			"using namespace " +
			"ciafb = <!http://www.cia.gov/cia/publications/factbook#>";

	// test query 4 (1 result)
	public static final String QUERY4 =
			"select Country, Name " +
			"from {Country} <ciafb:Name> {Name}; " +
			               "<ciafb:Map_references> {\"Africa\"}; " +
			               "<ciafb:Area_comparative> {\"slightly larger than Georgia\"}; " +
			               "<ciafb:Natural_resources> {\"petroleum\"}; " +
			               "<ciafb:Natural_resources> {\"iron ore\"}; " +
			               "<ciafb:Government_type> {\"republic\"}; " +
			               "<ciafb:Fiscal_year> {\"calendar year\"} " +
			"using namespace " +
			"ciafb = <!http://www.cia.gov/cia/publications/factbook#>";

/*--------------------+
| Methods             |
+--------------------*/

	public static void main(String[] args) {
		try {
			HTTPService service = new HTTPService(new URL(SERVER_URL));
			HTTPRepository repository = (HTTPRepository)service.getRepository(REPOSITORY);

			// Dummy runs to ensure classes are loaded, etc.

			System.out.println("Repository: " + REPOSITORY);

			System.out.println("Performing dummy runs");
			_timeQuery(repository, QUERY1, 10);
			_timeQuery(repository, QUERY2, 10);
			_timeQuery(repository, QUERY3, 10);
			_timeQuery(repository, QUERY4, 10);

			// Give JVM time to optimize stuff

			System.out.println("Waiting 2 seconds");
			Thread.sleep(2000);

			System.out.println("Starting measurements");

			float avgTime = _timeQuery(repository, QUERY1, 250);
			System.out.println("avg time for query 1: " + avgTime + " ms");

			avgTime = _timeQuery(repository, QUERY2, 250);
			System.out.println("avg time for query 2: " + avgTime + " ms");

			avgTime = _timeQuery(repository, QUERY3, 250);
			System.out.println("avg time for query 3: " + avgTime + " ms");

			avgTime = _timeQuery(repository, QUERY4, 250);
			System.out.println("avg time for query 4: " + avgTime + " ms");
		}
		catch (Exception e) {
			e.printStackTrace();
		}
	}

	private static float _timeQuery(HTTPRepository repository, String query, int iterationCount)
		throws Exception
	{
		QueryResultsTable queryResult = null;

		long startTime = System.currentTimeMillis();
		for (int i = 0; i < iterationCount; i++) {
			queryResult = repository.performTableQuery(QueryLanguage.SERQL, query);
		}
		long endTime = System.currentTimeMillis();

		return (endTime - startTime) / (float)iterationCount;
	}
}