[Qgis-developer] SpatiaLite very slow with QGIS 1.7

[a.furieri at lqt.it]

On Thu, 17 Mar 2011 18:48:51 +0100, MORREALE Jean Roc wrote
> Ticket #3002 may be linked, it is reproducible on windows/linux.
> 

Hi Jean Roc,

ticket #3002 isn't related at all to SpatiaLite
and/or to the QGIS own SpatiaLite data provider.

I've just attempted to save a (quite small sized) 
Shapefile as a SQLite DB following the procedure
reported on ticket #3002.

Yes, I can confirm, you are perfectly right: the 
export process is incredibly slow (> 10 minutes) 
and strongly inefficient (spatialite_gui performs 
the same identical task just in few seconds).

Anyway, at the end of the process a basic SQLite 
DB was generated. 
Please note well: this is *not* at all a SpatiaLite 
own DB; this one is an OGR/FDO own DB (a completely 
different thing, using an independent code base). 

So for sure this issue is entirely caused by OGR,
and has absolutely nothing to do with SpatiaLite.

Just as a working hypothesis: during this painful
export I noticed a very low CPU activity, and an 
impressively huge disk traffic.
This is exactly what I'm expecting from a badly 
implemented process attempting to perform lots and 
lots of SQL INSERTs without declaring a corresponding
BEGIN and COMMIT ... and such a condition notoriously 
is a real "performance killer" for any transactional 
DBMS. my 2 cents :-)

bye Sandro