Hello Andy, Thank you for your help.
The params I'm mainly interested in changing are those of the profile returned by StoreParams.getSmallStoreParams() to be able to reduce the dataset size. Except the test of changing the fileMode from mapped to direct, I've not made finer tuning on the other parameters, this is why the StoreParams.getSmallStoreParams() seems to be convenient for our needs. I've another question about this case: What will be the size result of changing from default store params to small store params on an existing TDB dataset ? I think this will have an effect on future writing (i.e. the existing size on disk will not be compacted -> is there a direct way or an existing tool able to compact the size of an existing dataset ?) Regards, Laurent On 26 August 2016 at 00:22, Andy Seaborne <[email protected]> wrote: > On 25/08/16 16:16, Laurent Rucquoy wrote: > >> Hello, >> >> I'm implementing a TDB-backed dataset (Jena 3.1) and I whish to provide a >> method to change the StoreParams of this dataset. >> > > > Because changing the StoreParams implies to release the corresponding > >> dataset location, I'd like to identify the current StoreParams in use to >> be >> able to avoid to release the location if the StoreParams we want to apply >> now are the same as those currently used. >> > > Release is not so bad unless you are doing it frequently. > > >> What is the right way to do this (if possible) ? >> > > This may work: > > DatasetGraphTDB x = TDBInternal.getBaseDatasetGraphTDB(myDatasetGraph) > StoreParams sp = x.getConfig().params ; > System.out.println(sp); > > (the "may" is because I only think it works on a live dataset no tested it) > > Obviously the name "TDBInternal" is a warning! > > Which params are you interested in changing? > > Andy > > Defaults: > > fileMode dft:mapped > blockSize dft:8192 > readCacheSize dft:10000 > writeCacheSize dft:2000 > Node2NodeIdCacheSize dft:100000 > NodeId2NodeCacheSize dft:500000 > NodeMissCacheSize dft:100 > indexNode2Id dft:node2id > indexId2Node dft:nodes > primaryIndexTriples dft:SPO > tripleIndexes dft:[SPO, POS, OSP] > primaryIndexQuads dft:GSPO > quadIndexes dft:[GSPO, GPOS, GOSP, POSG, OSPG, SPOG] > primaryIndexPrefix dft:GPU > prefixIndexes dft:[GPU] > indexPrefix dft:prefixIdx > prefixNode2Id dft:prefix2id > prefixId2Node dft:prefixes > > > >> Thank you in advance for your help. >> >> Sincerely, >> Laurent >> >> >
