Hi Raymond,

Can you show us the code doing this?
Do you commit features one by one ar all at once?

Best wishes,
Denis

On 07/29/2015 09:04 AM, 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?

Hoping anyone can explain!

Regards,
Raymond



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