Hi Jyoti, Virtuoso does not cache query result sets per say, but rather the databases working set for a given query work load gets loaded into memory (cache) on demand such that subsequent queries touching the same database working set would not have to be read from disk. Thus the first time a query is run the data is read from disk (“cold”) and may take sometime but subsequent runs where data is read from memory (“warm”) and will be significantly faster. See the Virtuoso RDF Performance Tuning Guide [1] for details on the INI file for tuning memory buffers available for caching the database working set and [2] for general performance tuning of the Virtuoso database. The key to performance being to have enough memory buffers to keep the database working set of the required query work load in memory at all time such that not disk access is required once the database is “warm” ie the working set cached is cached in memory.
[1] http://virtuoso.openlinksw.com/dataspace/doc/dav/wiki/Main/VirtRDFPerformanceTuning <http://virtuoso.openlinksw.com/dataspace/doc/dav/wiki/Main/VirtRDFPerformanceTuning> [2] http://docs.openlinksw.com/virtuoso/databaseadmsrv.html#ptune <http://docs.openlinksw.com/virtuoso/databaseadmsrv.html#ptune> 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 17 Sep 2015, at 16:12, Jyoti Leeka <jyo...@iiitd.ac.in> wrote: > > Dear All, > > I have the following question regarding Virtuoso 7.2. I'll be grateful if you > could help me with this a bit. Does Virtuoso 7.2 cache the query results > precisely and serves them back or does it cache the relevant portions of the > database and then recomputes the results? Also can we adjust the amount of > memory used by Virtuoso for caching. If yes, then how? > > > Thanks & Regards, > Jyoti Leeka > PhD Student > IIIT-Delhi > India > ------------------------------------------------------------------------------ > Monitor Your Dynamic Infrastructure at Any Scale With Datadog! > Get real-time metrics from all of your servers, apps and tools > in one place. > SourceForge users - Click here to start your Free Trial of Datadog now! > http://pubads.g.doubleclick.net/gampad/clk?id=241902991&iu=/4140_______________________________________________ > Virtuoso-users mailing list > Virtuoso-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/virtuoso-users
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