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?
Hoping anyone can explain!
Regards,
Raymond
--
Terglobo
Ampèrestraat 110
5223 CT 's-Hertogenbosch
The Netherlands
+31 6 25 31 49 83
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