Hi Raymond, On 29/07/2015 09:04, Raymond Nijssen wrote: > Dear developers, ;) > > A plugin of mine imports data from a gml file into a memory layer. Works > fine for tiny gml files, but takes forever on huge ones. Sounds > plausible maybe, but the relation is not linear. > > So I did did some tests and found out that reading and parsing the gml > and creating the features always goes at the same speed of about 400 > features a second (fps). But when adding these to my memory layer, the > process slows down tremendously. > > I output the fps for every 1000 features and it gave me this graph: > > http://terglobo.nl/downloads/memory-layer-performance.png > > At the end of the importing process I'm processing just 3 features per > second. > > Is this expected behaviour? Is a memory layer not meant for something > like this? Or is this a bug? > > In the source code I found that for every feature I add to a memory > layer the index is updated. Could that be inefficient?
If I am correct the spatial index is created only if you ask so (by passing "index=yes"). Do you have the same results without spatial index ? _______________________________________________ Qgis-developer mailing list Qgis-developer@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-developer
