Tangentially on JDBC/ODBC vs HTTP. HTTP is slow because of the transport, but JDBC/ODBC has more mature models of paging over results, pre-fetching, etc. I feel that RDF is mature as a Data format, but as a protocol it is not that mature.
-----Original Message----- From: Hugh Williams [mailto:hwilli...@openlinksw.com] Sent: Monday, September 12, 2016 5:30 AM To: Lorenz Buehmann <buehm...@informatik.uni-leipzig.de> Cc: virtuoso-users@lists.sourceforge.net Subject: Re: [Virtuoso-users] Out of curiosity, some questions about OpenSource Virtuoso settings Hi Lorenz, In Virtuoso 7+ Vectored query execution [1] enables single, typically complex analytical types queries, to be broken down and executed on multiple threads. The INI file param that controls this is "ThreadsPerQuery" [2] , which controls the maximum number of threads that can be claimed from the thread pool by a single query, and there are other associated params details at [2] . [1] http://docs.openlinksw.com/virtuoso/vexqrparl.html [2] http://docs.openlinksw.com/virtuoso/vexqrparlconfp/ Best Regards Hugh Williams Professional Services OpenLink Software, Inc. // http://www.openlinksw.com/ Weblog -- http://www.openlinksw.com/blogs/ LinkedIn -- http://www.linkedin.com/company/openlink-software/ Twitter -- http://twitter.com/OpenLink Google+ -- http://plus.google.com/100570109519069333827/ Facebook -- http://www.facebook.com/OpenLinkSoftware Universal Data Access, Integration, and Management Technology Providers > On 12 Sep 2016, at 07:13, Lorenz Buehmann > <buehm...@informatik.uni-leipzig.de> wrote: > > Hi, > > just as a follow-up question: > > I know it supports inter-query parallelization, but does it also support > intra-query parallelization, i.e. using multiple threads to compute the > result of a single query? If yes, which parameter is used to configure this? > > > Cheers, > > Lorenz > > On 12.09.2016 05:57, Kingsley Idehen wrote: >> On 9/10/16 10:41 PM, giacom...@libero.it >> wrote: >> >>> So, I have a bunch of questions about Virtuoso. >>> >>> * Are SPARQL queries performed concurrently (using the standard >>> virtuoso.ini configuration)? >>> >> Yes, Virtuoso is highly multi-threaded. In addition, it has >> vectorized query execution i.e., many query batches per thread, handled >> concurrently . >> >>> * Are Virtuoso transactions autocommittable, or there aren't any >>> kind of transactions when connecting to the ODBC driver? >>> >> Depends, by default you have Read Committed Isolation level. >> >>> * Does Virtuoso automatically performs triple indexing before query data? >>> >> No, it has indexes in place. >> >> >>> In >>> some systems I have to configure it manually. >>> * Does the usage of ODBC degradates the benchmarking of Virtuoso's >>> SPARQL query or the time required to store the triples within a given named >>> graph? >>> >> No, if anything that's faster than HTTP. >> >> Links: >> >> [1] >> http://docs.openlinksw.com/virtuoso/isolation/ >> >> [2] >> >> http://wikis.openlinksw.com/VirtuosoWikiWeb/ChangeVirtuosoSDefaultTra >> nsactionIsolationLevel >> >> [3] >> http://docs.openlinksw.com/virtuoso/fn_log_enable.html >> >> [4] >> >> http://virtuoso.openlinksw.com/dataspace/doc/dav/wiki/Main/VirtRDFPer >> formanceTuning >> >> >> [5] >> >> http://virtuoso.openlinksw.com/dataspace/doc/dav/wiki/Main/VirtBulkRD >> FLoader#Running >> >> multiple Loaders >> >> >> Kingsley >> >> >>> Thanks in advance for any support, >>> >>>> JackB >>>> >>> -------------------------------------------------------------------- >>> ---------- _______________________________________________ >>> Virtuoso-users mailing list >>> >>> Virtuoso-users@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/virtuoso-users >>> >>> >>> >> >> >> >> --------------------------------------------------------------------- >> --------- >> >> >> >> _______________________________________________ >> Virtuoso-users mailing list >> >> Virtuoso-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/virtuoso-users > > ---------------------------------------------------------------------- > -------- _______________________________________________ > Virtuoso-users mailing list > Virtuoso-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/virtuoso-users ------------------------------------------------------------------------------ _______________________________________________ Virtuoso-users mailing list Virtuoso-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/virtuoso-users
