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https://issues.apache.org/jira/browse/JENA-2228?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17464463#comment-17464463
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Andy Seaborne commented on JENA-2228:
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bq. So if the dataset is small enough (12KB in my case), then it can be stored
entirely in a cache?
The cache is for RDF terms, not triples.
Caching for triples happens below the B+Trees (in the OS file system cache).
bq. used for querying
See {{OpExecutorTDB2}} and {{PatternMatchTDB2}}.
bq. given a Node as parameter
The node table. Easiest to go via {{TDBInternal}}.
> Does Fuseki2 use TDB indexes or indexes for in-memory store?
> ------------------------------------------------------------
>
> Key: JENA-2228
> URL: https://issues.apache.org/jira/browse/JENA-2228
> Project: Apache Jena
> Issue Type: Question
> Components: Fuseki, TDB
> Affects Versions: Jena 3.17.0
> Environment: I am running the jena-fuseki-server-3.17.0.jar file from
> jena-fuseki2/jena-fuseki-server/target/ as follows
> {code:java}
> java -Xmx500g -jar fuseki-jenaclone.jar --tdb2 --loc=db/jena
> --timeout=1000000 /jena &{code}
> Reporter: Martin Pekár
> Priority: Major
> Fix For: Jena 3.17.0
>
>
> Based on logging messages inserted into various places in the indexes in the
> TDB module (NodeTupleTableConcrete, TupleIndexBase, NodeTableNative,
> BPlusTree), I can see that the B+ tree is only used once per query. I have
> inserted logging messages for every finding method to see which classes are
> used when querying. I would expect to the the B+ tree be used several times
> per query.
>
> I use the error logging level, and I inserted logging in the class
> constructors to make sure logging worked. I see construction of all the index
> classes.
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