[EMAIL PROTECTED] ha scritto: ... > See the debug info : > > [DEBUG_GeoCodageExcelWizard_16:47:04 453] Start 338 check feature > collection here > [DEBUG_GeoCodageExcelWizard_16:47:04 484] End 338 check feature > collection here > => 31ms to apply the filter and query. > > > When I put this layer in Memory (By creating a a new Layer in udig with > MemoryDataStore) performances are much better!! > > [DEBUG_GeoCodageExcelWizard_16:51:40 187] Start 338 check feature > collection here > [DEBUG_GeoCodageExcelWizard_16:51:40 203] End 338 check feature > collection here > => 16ms > > I would like to know if such a difference is normal, and how way could > we reduce calculation time by other way than creating a new 'in memory" > layer?
Reading stuff from memory instead of disk is definitely faster, no doubt about it, the disk is the slowest part of your pc. Yet, the benchmarks above are useless, a matter of milliseconds can be influenced too much by external stuff such as background running tasks on your pc (mail checking, antivirus, whatever). A good bench must take some tens of seconds to make sure. Anyway, the result above won't change, if you have enough memory and do not do spatial filters the memory data store will always be faster. Postgis and other database will become faster than memory only if your dataset is big and the database can use indexes to solve queries, otherwise the extra machinery (network protocol, transaction management, and so on) will definitely make those slower than a memory data store. Cheers Andrea Aime ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys -- and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Geotools-gt2-users mailing list Geotools-gt2-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users
