pwiederm...@googlemail.com wrote: > Hello! > > I think the major performance options for virtuoso are > NumberOfBuffers, MaxDirtyBuffers, MaxCheckpointRemap. Is that correct?
Yes these are certainly important. > I think loading time is too long in my tests: > > load dbpedia articles_label_fr.nt (~ 253200 triples) started 30 min > ago and is not finished. > My machine is a intel core dual 2Ghz with 4GB RAM and one SATA disk > under linux. the hard disk is very very busy while the import. can > this be tuned? > > I tryed the default values in virtuoso.ini and > > Database] > ... > MaxCheckpointRemap = 400000 > ... > > [TempDatabase] > ... > MaxCheckpointRemap = 20000 > ... > > ; > ; Server parameters > ; > [Parameters] > ... > NumberOfBuffers = 180000 > MaxDirtyBuffers = 120000 > AutoCheckpointLogSize = 10000000 > ... > > I also tryed NumberOfBuffers = 100000 > > at the beginning top reports much free memory for a long time , after > ~ 45 min it is: > > Mem: 3984900k total, 3957004k used, 27896k free, 11416k buffers > Swap: 6385796k total, 268k used, 6385528k free, 2111984k cached > > 5362 peterw 18 0 1944m 1.6g 9520 S 1 41.7 2:07.61 virtuoso-t > > Can you give me hints what i can change to improve performance? > Hi, Two questions: a) what's your checkpointinterval setting? Might be advisable to disable that until after it's done. b) what function(s) are you using to do the import? If you're not using it, DB.DBA.TTLP_MT() is multi-threaded - more docs at http://docs.openlinksw.com/virtuoso/rdfapiandsql.html . HTH, ~Tim -- Tim Haynes Product Development Consultant OpenLink Software <http://www.openlinksw.com/>
